Sure for me too the Amiga are A1000/500/CDTV/2000/3000/600/1200/4000...
Mostly because of Nostalgia, AmigaOS4, Morphos, ARos are Amiga because they're to some degree highly compatible OS wise to AmigaOS 3.1 (not HW wise).
Why not rewrote the Window/input/ouput.. stuff in C, like creating an IDE then use vasm assembler to produce the code for all the processors we want ?
Sure it will be slower on classic Amiga, but they'll be better for the future and now most good C compiler do produce a better code than a human. (that's another topic, many will not agree, sure it may not be true for 68k but look at G5 multicore processor, bi-core, quad-core etc.)
vasm : http://sun.hasenbraten.de/vasm/