I do miss 2e, warts and all. While I certainly appreciate the d20 mechanic, I do find I miss all the disparate resolution mechanics possessed by 2e from time to time. Granted looking back it appears sloppy, unwieldy, warty and ugly...but it worked well enough and I did (and do) enjoy the variety that brought. Of course my groups played so frequently it became second nature to know which required high rolls, which required low rolls, or percentile, etc.
Of course, we did house rule the crap out of 2e. We ignored racial level limits. We switched dual-classing and multi-classing (we always felt that was backwards and that short-lived humans would be more likely to multi-class and the longer lived demihumans would dual class). We did eventually just get rid of dual-classing and allowed humans to multi-class in whatever combo they liked (max. 3 classes, conflicts we'd deal with if they came up and demihumans kept their usual limits on what classes they could multi-class). We got rid of certain racial weapon bonuses (elf getting +1 to long/short swords and bows, halfings with slings) and just gave those races a single free weapon prof, even if it might violate class restrictions (we found it never caused an issue). We gave Humans and Half-elves a +1 to an ability score of the player's choice at character creation. Everyone's 1st level HP was their CON score (later levels followed the usual rules). There were a ton more.
A big part of it too was there was so much product to choose from. It got crazy and unsustainable, sure, and some of that product was absolute crap (and some just broke things...looking at you Complete Book of Elves), but damn it was a good time.