My son was diagnosed 6 years ago and was put on Novomix 30 and has stayed on it. He accepts the advice given him and is happy with his control.
I was diagnosed in Feb this year initially as Type 2 so went straight on Low Carb. Didn't like results and managed to get myself reclassified Type 1. Was put on Novomix 30 and achieved HbA1c of 5.1 but after 3 months asked to try Levimir + Novorapid as still not happy with some of the swings. Results not a lot better - still get swings - injections up from 2/3 per day to 5/6 per day and plagued by what could be early morning liver dumps.
Changing in theory does give you the option of better correction but does need greater input from you I feel.
Sorry if I've not really answered the original post re explanation of insulin types but generally fall in to class of mixed ( Novomix), Rapid acting (Novorapid etc.) and Basal (Levimir etc).