dRu- i have a stock na rev1 however i have done some work on quite a few mates cars although im still learning all the time but!
if your car was mine and had the spare cash i would definately go the suspension route first as this will greatly affect what rims you can actually fit on your car depending what coilovers you get, also you will have a lot more fun in your car with a full suspension upgrade namely: (again if it were my car)
Coilovers (what ever floats your boat dont get too harsh though otherwise your teeth will fall out if its a daily and adelaide roads are pretty piss poor)
FRONT anti sway bar whiteline/trd/etc apparently on an mr2 upgrading the front sway bar will have a greater effect compared with the rear (this info comes from Chameleon) but if you have some cash to burn then get the set but be careful to get the right size as different rev/gen sw20 mr2s have different length sway bars!!!
strut braces- go the trd ones especially for the rear as few aftermarket strut braces are four point like the trd one (these are quite expensive though compared with other brands of strut braces around 500-650AUD delivered??)
After that i would be looking at getting some nice wheels to set off your ride as there is nothing worse than buying one set of rims and then having to buy another set after you have upgraded the suspension due to rubbing on the guards when turning
If i was going to buy some rims i would always value width before height as width greatly effects your road grip (dry conditions) but be careful as the wider the rims the LESS grip you will have when its really wet and on dirt roads