Hi Echelon, nice to have you with us
You'll want to get yourself at least 32MB Fast RAM to replace that 8MB SIMM, especially if you're going to be running OS3.9 (with its dog-slow datatypes).
And how about an Indivision AGA? I'll tell you what, running Workbench in 1024x768 is way better than 640x256. And the convenience of being able to plug your A1200 into any kind of monitor (VGA/RGB/LCD/TV) is great.
If you have time, you should come on IRC and chat to us, we're a friendly bunch mostly.