Learn about the Amiga and what it can do in its present state, then slowly add the upgrades and see how they improve things! There's so much choice now isn't there - choice is good. See what you can get out of 1.2 before moving onto 3.2. It's better not to have gaps in your knowledge. I started with an A1200, but I went back to A500 years later and learned all about 1.3 etc.
I have an A500 with a Megabody IDE controller + real HDD (which works with 1.3) and 512K in the trapdoor (total 1MB Chip). It would be nice to add a Kickstart switcher for me in the future so I can get the best of both worlds - 1.3 and 3.2, but it's all boxed up at the moment due to space shortage. It takes you back to 1990, so it's like a time machine when that thing boots up.
I'd probably favour the IDE/8 MB FASTRAM/OS3.2 setup now, as I can't easily add REAL Fast RAM to my A500 with the Megabody, if at all (I don't favour the zorro slot as it eats space). I have one of those GARY adapter things to get slow RAM but... you get the picture. As you know, there are other processor upgrades for the A500, but personally I see it as a 68000 or 68010 machine and mine will be staying that way. Just what can the 68000 do at 7MHz, what can be achieved? That's the fun in it to me, the limitation (knowing I have a beefed-up A1200 of course).