imho if you enjoy classic Amigas and want to really trick one out, get a big box 2,3,or 4000.
Build from a system that was manufactured to expand.
Zorro slots are real nice to build off of and are more stable than a small box amiga with tons of add ons. I had a 1200 and it was great for certain things and fun to play with, once I got into add on's it was a headache I didn't enjoy.
Super Buster 11 is your friend for maxing out a system and the 3/4000 have a great bus to build from and make a huge difference if you want a fast performing system. Not having a Buster with the mediator isn't worth it to me...
But hey this is an emotional journey, if you want to trick out a 1200 go for it... Lot of Amiga users do and enjoy the experience, I just never did...
About the only advantage for going pci is the better DVI output for graphics cards, but you loose the auto switching zorro cards.