I have the exact same curl type as you, My top most layer is all super curly 3a and below that is the 2c and even below that is all the 2a's. I always self cut my hair. But the way I do it is, I do put a lot of layers in the 2c-2a,I would put in layers in the 3a , but not anything dramatic.
The reason I do it this way is because of the curl pattern, my almost level cut hair would even look like I have had some layers after I have styled it - because of the different curl pattern, If that makes any sense at all.
Hope this information helps
3a with some 2a-2c, Medium/Low Porosity
Co-wash:deva no-poo/Vo5 kiwi
Leave-in:Shea Moisture/GVP conditioning Balm/AOHSR
Since long hair- I finger twist in big chunks, which helps till 5th day hair
Plop: Old T-shirt for 15 minutes ,diffuse