@MacMiga:
HARD DISK
I never heard about overheating problems, and I know a lot of guys who run 1-4 gig HD inside their A1200.
Keep in mind that the A1200's IDE port is not very fast though.
CD-ROM - I have a SCSI external from my Mac side of things. Is it easy to get a CD drive working on an old Amiga?
Yes. The CD file system included with OS 3.1 is crap though. Better upgrade to 3.9 or use a third party CDFS.
anarchic_teapot says the PCMCIA Squirrel card can cause unstable OS type problems. Any thoughts?
Squirrel is crap (by today's standards). Very slow - and you will want to use the PCMCIA port for a NIC anyway.
Any other SCSI options for the A1200?
Get a accellerator card with SCSI onboard (see below)
HI-RES GFX
That's your biggest problem. Unless you want to put the whole computer in a tower case and either use a PCI bus board or a BlizzPPC/BlizzVision combo, you don't have access to a gfx card (not: the BPPC/Bvision will *not* work in a desktop case).
Your best option would be to get a scandoubler+flickerfixer. This will give you 640x512 with 256 colors (but you should restrict yourself to 64-128 colors, 256 is way to slow) on any standard VGA monitor.
FASTER CPU
Either get a Blizzard 1230 or a Blizzard 1260: Brilliant hardware. Don't forget to get the accompanying SCSI module.
1230: barely enough horsepower to run current apps (modern games, WWW, graphics stuff etc.), but good for some retro fun.
1260: All the power you need (AmigaOS is
a lot faster than MacOS)
AMIGA OS 3.9
You should have a 68030 at least. GFX card is highly recommended, but it will work with AGA.
NETWORKING
Yes, get a PCMCIA NIC. Forget about the squirrel, better get an accellerator with a SCSI module (it's probably ten times faster *without* eating much CPU power (like the squirrel)).