Insurance costs - its worth noting you can insure the e30s as a classic car with some companys which means cheapness
E36s seem to be cheaper than good e30s - and 325 saloons can get picked up for around 450 with tax and ticket if your not in a rush to get one.
I couldnt decide between the 2 myself - I love my e30 now it has brakes
- but I do miss my e36 but never tried to skid it then so cant compare them in that aspect.
E30s engine is sooo easy to work on though. And the main thing I dont like about mine is the steering (can solve with an e36 or z3 rack) and the trailing arm rear suspension (although it seems more robust than the E36 Z axle)