It's a pain in the ass, just like any other homebrew on an old console that wasn't an open platform.
6502 based assembly is pretty wacky. Other systems are easier, believe it or not. Z80 based machines for example. Z80 assembly is cake.
Fortunately, if you know C, you can do that on the PCE and be alright.
The dev-tools for PCE aren't the best. HuC has some problems. Fortunately there are enough examples out there, and enough helpful people that you should be ok.
Tools you will need:
HuC (the only C compiler for the PCE)--->
www.zeograd.comIt also comes with MagicKit's pceas which is the Assembler for the PCE
Squirrel, if you plan on making chiptunes for your game without hurting yourself ---->
www.aetherbyte.com/psg.htmMednafen, for debugging your stuff.
http://mednafen.sourceforge.net/ You also need a paint program that accepts .pcx files. The 4 plane DOS variety. I personally recommend NeoPaint. Photoshop does some stupid crap with the palettes, and makes it more work.
For Insanity, we used the following tools:
Squirrel (since we kinda wrote it here at Aetherbyte)
HuC w/ alot of optimized 6502 assembly
NeoPaint
DaemonTools (to mount CD ROM images for emulators)
Ootake (a nicer to navigate emulator)
Mednafen (for debugging)
Ask questions here, or try the forum at
www.aetherbyte.com We usually check and answer stuff.
I also have a #pcedev channel on Efnet if you use IRC. You can try #utopiasoft also, but I personally don't recommend it anymore. It's devolved a bit. Maybe it got better. I don't care enough to check.
Zeograd.com has alot of open source examples you can check out
ArchaicPixels.com has a pretty decent explanation of HuC's stuff.
In any event, I suggest you stick it out and dev for the PCE. We need more people.