The first four systems I can remember playing are Villains and Vigilantes (high school), Champions (1st year college club), and Over the Edge and Mage (game shop where I really started to become a 'gamer').If I may ask, what were your other RPG starters and your early formative? Not D&D is just as interesting to me. I started with AD&D but black book Traveller was as big for us early.
Early years included things like Call of Cthulhu, Paranoia, Kult, Whispering Vault, Nephilim, Elric, Immortal, Ars Magica, Pendragon, Lace and Steel, Castle Falkenstein, Bushido, and Amber. Probably others I'm forgetting. Playing several games a week gave a lot of opportunity for experimenting with various systems, and there were a lot of fun things in each of their settings.
So the primary game styles were: superhero, supernatural, horror, and period fantasy. Got into some cyberpunk and sci-fi systems a bit later. The period fantasy systems largely supplanted any need or desire for D&D, though the very first (and only non-5E) D&D game I played in could also be considered a period fantasy setting: Al-Qadim.
On the mechanics side, the fluidity of the magic systems in games like Mage, Ars Magica, and Castle Falkenstein always made the D&D magic system feel horribly stilted and clunky. I'll also admit that the wall of extended rule books for D&D turned me off as well.
I did still enjoy all the various D&D novels, though.