I've been through all of your various thought processes you've raised in your post and am still regularly challenged by most of them as I progress in my diet/lifestyle changes. You're definitely not alone!
As we all know because we're taught it in school - one of the basic rules of good science is to only change one variable at a time, test, then determine next steps. Since diagnosis, I've changed multiple factors, all at once, and very quickly for the first 6 months - lowered BG, lowered hba1c in turn, lost significant amounts of weight, completely changed my diet, added far more exercise/activity into my life...and so on. Each of those areas has numerous sub-categories, considerations and decisions to be made too. There have been so many changes, in such a relatively short period and with so many considerations at play, it can be difficult to focus on what to do when it comes to balancing all of the factors involved. It's also a neverending, shifting set of considerations, as various factors change along the way. Sounds like you've had a similar experience since going the diet management route. My best advice here (which I'll admit I'm generally terrible at following
), is to try not to stress, to try to keep an eye on high level goals and resist the temptation to get lost in the detail, and to give yourself credit for your many positive achievements rather than looking for flaws/failures. As you said, it's a journey, and part of that journey is allowing yourself to feel a sense of achievement rather than it being an endless quest for improvement.
To pickup on some specific points you raised:
Protein: Quantity - I'm far from an expert on this. It's a contentious topic in the keto arena, let alone nutrition more broadly. My layman's understanding is that most people need 0.8g to 1.5g per kg of ideal body weight, depending on a variety of personal factors. More than 1.5g only seems to be beneficial if you're looking to build muscle and are weight training accordingly.
Protein: Glucose - Although protein can be converted to glucose via gluconeogenesis, this is a demand driven process, which is utilised as needed. According to a number of sources I've read, it isn't triggered by the supply of protein via diet. Unless consuming very large quantities of protein, it's unlikely to affect ketosis and/or BG significantly from what I've read. For keto purposes, it's also generally stated that carb and fat macros are limits, protein is a minimum target.
Dawn phenomenon - This is a common topic here on the forum and it's almost entirely caused by your liver dumping glucose into your system. Our livers, while amazing organs for what they're capable of, are unfortunately also stupid. Our livers aren't aware of diabetes or insulin resistance, so go about their business in the morning of waking us up, giving us the energy we'll need to walk 10 miles hunting for food and fighting off a T-Rex along our way. It doesn't realise we have a fully stocked kitchen, in the safety of a locked house, just a few steps from where we were wake up. There are some things we can do to help mitigate/reduce dawn phenomenon:
1) Losing weight can help, specifically visceral fat, as NAFLD can exacerbate dawn phenomenon.
2) If you eat a small, low carb food item or meal, it will often cause your liver to stop dumping glucose (something like a boiled egg or some cheese works for me). Ultimately though, directly controlling what our livers do isn't possible, so many of us here don't stress about it too much and some don't monitor/track BG readings first thing in the mornings.
Fasting - There are far more experienced people with this topic than me here. I do overnight 16:8 and 18:6 intermittent fasting, but I don't have a religious schedule with it. If I'm hungry, I have breakfast, if I'm not then I don't. I use it as a tool to control my snacking urges in the evening, plus it does help with controlling/improving NAFLD from what I've read. If you're concerned about dawn phenomenon though, it's possibly worth just balancing fasting with ensuring your BG levels don't get out of hand.
Portion control / cravings / relationship with food - I've been on a significant learning curve with these areas over the past 10 months. Historically, I've been dreadful with these on all counts. When I made the decision to manage T2D using diet, it forced me to confront many of my food demons. For the first 3-4 months, I went on a strict keto diet, less than 20g carbs per day. I had banned foods, that I just didn't go near, nor did I didn't particularly seek out low carb alternatives for pasta, rice etc. My cravings significantly reduced during this period and I learnt how to portion control. I reduced my hba1c from 83 to 32 in this initial period and resolved a lot of health complications and T2D symptoms along the way. From that point, diet sustainability and longevity became an increasingly important factor. From 4 months, I moved to generally eating 20-30g carbs per day, occasionally up to 40g. Not a huge change, but it offers more flexibility and that was important to me. I don't have banned foods as such, but I do use a lot of low carb alternatives/substitutes for carby foods, e.g. low carb breads, low carb pasta, low carb rice, dark chocolate, low carb cakes etc. Pretty much my only banned food, that I don't have a decent substitute for, is potato. For me, this approach has helped me stay on course and my recent hba1c was in non-diabetic range again.
Out of all I've written in this very long reply (apologies), the last point has been the most critical one for me. Improving my relationship with food and all that comes with doing so has helped me in so many ways.
As we all know because we're taught it in school - one of the basic rules of good science is to only change one variable at a time, test, then determine next steps. Since diagnosis, I've changed multiple factors, all at once, and very quickly for the first 6 months - lowered BG, lowered hba1c in turn, lost significant amounts of weight, completely changed my diet, added far more exercise/activity into my life...and so on. Each of those areas has numerous sub-categories, considerations and decisions to be made too. There have been so many changes, in such a relatively short period and with so many considerations at play, it can be difficult to focus on what to do when it comes to balancing all of the factors involved. It's also a neverending, shifting set of considerations, as various factors change along the way. Sounds like you've had a similar experience since going the diet management route. My best advice here (which I'll admit I'm generally terrible at following

To pickup on some specific points you raised:
Protein: Quantity - I'm far from an expert on this. It's a contentious topic in the keto arena, let alone nutrition more broadly. My layman's understanding is that most people need 0.8g to 1.5g per kg of ideal body weight, depending on a variety of personal factors. More than 1.5g only seems to be beneficial if you're looking to build muscle and are weight training accordingly.
Protein: Glucose - Although protein can be converted to glucose via gluconeogenesis, this is a demand driven process, which is utilised as needed. According to a number of sources I've read, it isn't triggered by the supply of protein via diet. Unless consuming very large quantities of protein, it's unlikely to affect ketosis and/or BG significantly from what I've read. For keto purposes, it's also generally stated that carb and fat macros are limits, protein is a minimum target.
Dawn phenomenon - This is a common topic here on the forum and it's almost entirely caused by your liver dumping glucose into your system. Our livers, while amazing organs for what they're capable of, are unfortunately also stupid. Our livers aren't aware of diabetes or insulin resistance, so go about their business in the morning of waking us up, giving us the energy we'll need to walk 10 miles hunting for food and fighting off a T-Rex along our way. It doesn't realise we have a fully stocked kitchen, in the safety of a locked house, just a few steps from where we were wake up. There are some things we can do to help mitigate/reduce dawn phenomenon:
1) Losing weight can help, specifically visceral fat, as NAFLD can exacerbate dawn phenomenon.
2) If you eat a small, low carb food item or meal, it will often cause your liver to stop dumping glucose (something like a boiled egg or some cheese works for me). Ultimately though, directly controlling what our livers do isn't possible, so many of us here don't stress about it too much and some don't monitor/track BG readings first thing in the mornings.
Fasting - There are far more experienced people with this topic than me here. I do overnight 16:8 and 18:6 intermittent fasting, but I don't have a religious schedule with it. If I'm hungry, I have breakfast, if I'm not then I don't. I use it as a tool to control my snacking urges in the evening, plus it does help with controlling/improving NAFLD from what I've read. If you're concerned about dawn phenomenon though, it's possibly worth just balancing fasting with ensuring your BG levels don't get out of hand.
Portion control / cravings / relationship with food - I've been on a significant learning curve with these areas over the past 10 months. Historically, I've been dreadful with these on all counts. When I made the decision to manage T2D using diet, it forced me to confront many of my food demons. For the first 3-4 months, I went on a strict keto diet, less than 20g carbs per day. I had banned foods, that I just didn't go near, nor did I didn't particularly seek out low carb alternatives for pasta, rice etc. My cravings significantly reduced during this period and I learnt how to portion control. I reduced my hba1c from 83 to 32 in this initial period and resolved a lot of health complications and T2D symptoms along the way. From that point, diet sustainability and longevity became an increasingly important factor. From 4 months, I moved to generally eating 20-30g carbs per day, occasionally up to 40g. Not a huge change, but it offers more flexibility and that was important to me. I don't have banned foods as such, but I do use a lot of low carb alternatives/substitutes for carby foods, e.g. low carb breads, low carb pasta, low carb rice, dark chocolate, low carb cakes etc. Pretty much my only banned food, that I don't have a decent substitute for, is potato. For me, this approach has helped me stay on course and my recent hba1c was in non-diabetic range again.
Out of all I've written in this very long reply (apologies), the last point has been the most critical one for me. Improving my relationship with food and all that comes with doing so has helped me in so many ways.