I dont think the APSC cameras will be any faster than an RP in terms of AF, both
@addicknchips and I come from what are arguably the fastest AF MILC cameras the A7iii and A9 and we both regard the RP as excellent (or we wouldnt keep them because we dont hang onto cameras we dont like), its great EF lenses behave like they do natively on a DSLR with the added benefit of OSPDAF. As he said though, the only real thing letting it down is the FPS, AFC youre looking at 4 FPS, AFS 5FPS. Battery life is well under rated, I get nearly 1000 shots and still have juice left.
4K youll get a big crop, looks like theres a new speedbooster which eliminates it or shoot EFS ultra wides like the 10-18 for wider stuff.
Crop mode is fine, its just a drop in MP. IQ is still great.
The fully articulating LCD is really nice, more manufacturers should do it, ergonomics are also great.