I understand what you mean. At this point an e36 almost certainly wouldn't be a daily driver, but having had both e36 and e46 alongside one another, several times, (admittedly, not M's but 325i/328i alongside 330Ci and 330Ci Sport), I'd see the e36's as being even more "involving". Whenever I've had to choose which one to keep, the e36 won every time. The limits are definitely lower, given that the e36 design is almost 30 years old. I suppose it depends of personal priorities when you balance all the aspects of performance, driving pleasure and costs/practicality.