I'm a little biased but I'll share what I know about them.

Toyota is known for their bulletproof cars and the mr2 is not an exception. The only problem is that, like what they said^^^, they are hard as fuck to work on. Being a mid engine car, you have limited access to many parts.. but like other cars.. pulling the engine would make your life a lot easier.

The 3sgte is an amazing engine and parts are plentiful. If you want to go fast, power to weight will only get you so far with the 5sfe from the N/A... but there are pros and cons of being N/A (i.e. insurance, gas mileage, reliability).Their handling is amazing due to the weight distribution; however Turbo models and 93+ got better suspension than the N/A 91-92's.

That said, they're fun little cars. Opt for a 93+ since the 91-92 had quite a few problems that they sorted out in 93. Likewise, t-top will inevitably leak so opt for a sunroof or if you could find one, a hardtop.

If I were in your shoes, I'd get a N/A, drive the shit out of the 5sfe and then do a swap. The cookie cutter thing to do would be to do the 3sgte turbo swap. If you want to be a little more unique, do a v6 swap. If you want to be super fucking jdm tyte.. BEAMS (the toyota equivalent of a b18c with super vtec IMO)