I did not like that part of it.

Personally I've standardized on just three STM32 parts:

* L031 for throwaway-cheap stuff where I'm never going to do field firmware updates (so no need to burn flash on a proper bootloader) and just need to toggle some GPIOs or something

* L431 for most "small" stuff; I use these heavily on my large/complex designs as PMICs to control power rail and reset sequencing. They come in packages ranging from QFN-32 to 100-ball 0.5mm BGA which gives a nice range of IO densities.

* H735 for the main processor in a complex design (the kinds of thing most people would throw embedded Linux at). I frequently pair these with an FPGA to do the heavy datapath lifting while the H735 runs the control plane of the system.