Hello paulpapa!
Here are my thoughts:
Firstly and most importantly, whatever adjustments you decide to make in relation to your insulin, should always be in collaboration with your doctor/diabetes nurses. In this forum we are sharing thoughts or suggestions but, we are in no way able to make a suggestion on someone’s insulin regime.
Having said that, I will divert you to the following website:
http://www.diabeticretinopathy.org.uk/prevention/insulindoseinsulin.htm
As a general rule, (as you will also read in this website) background insulin is determined by body mass (and other parameters such as exercise/activity for example.) Most people need a total of 0.5 - 0.8 units of insulin per kilogram of body weight each day. Roughly half this insulin is needed for food intake (Novorapid) and half is the basal rate (Levemir). Sometimes it can be 40% Levemir and the rest Novorapid, but this is the general idea.
In my view, before you experiment with anything else (like a low carbohydrate diet, vegan/vegetarian diets or bolusing for protein/fat) make sure that your Levemir is correct. If your background insulin is not correct then, nothing works well.
I would suggest that you go through a series of basal tests to determine if your Levemir dosage is correct of if it needs reduction. I suggest that you discuss your findings with your diabetes nurse/doctor.
Do you know how to run a basal test?
As soon as you have your Levemir dosage correct then everything else becomes more manageable.
I also do not suggest that you switch to Tresiba, at least not before your find your correct basal rate. The reason is that Tresiba takes about 4 days to give a steady state (being an ultra long-acting insulin). If you hypo on Tresiba and you realise that you need to reduce your dosage, you will be running after hypoglycemias for 2-3 days until your new dosage kicks in.
Keep in mind that, generally, Tresiba is more aggressive insulin and it is very possible that you will need less amount than Levemir.
I hope this helps.
Regards
Josephine