I put most of the logic in C++. All my BPs have C++ base classes so I can decide on a case by case basis what should go where. A lot of my test members vars might only be in bp for example. Hot reload for compiling C++ has improved alot but is still not perfect. I highly recommend a SSD if you’e using C++. It was unbearable on a mechanical drive. So, use both. If you want to try something real quick you can throw it together in BP and then move to C++ later. I tend to always start in C++ though but that’s just me.