It really depends on your skillset as to whether or not an AW11 is a good fit or not. (a poor example at least anyway)
I've built a couple of Classic V8's which are far simpler (for the most part) than an MR2. However the MR2 is much better documented for every nut and bolt than many classics out there. (Using gregory's or the BGB to guide you through)
I'd try to buy yourself a decent example. aim to buy one that has good fundamental components. (IE: Engine and trans in good nic, all interior parts are there etc) - The older cars get, the harder it is to source decent parts.
from a solid and complete base car you can give your car a new lease on life through some wrenching time. - Replacing suspension bushings and components, upgrading the engine through simple upgrades, servicing it up, restoring old interior parts etc.
I find the process fun when you have time. If you are rushing though, things just turn to S#!t everytime.
Make sure to post up if you buy one. fantastic choice in car that will give years of fun.