I've got some titles I think you should check out. These are some from my collection that you didn't have on your list.
Sonic Spinball - This is often over looked, not sure why. I love this game.
Castlevania Bloodlines - You can't be a Castlevania fan and not have this game.
Mortal Kombat II - Even though you have one and three, this is still a great game.
Super Street Fighter 2 - My favorite flavor of the Street Fighter 2 series.
Streets Of Rage - People argue over which is better, 1 or 2. I like the first just a hair more.
Streets Of Rage 3 - Not as good as the first two, but still kick ass fun.
Golden Axe - Streets of Rage in medieval times.
Golden Axe 2 - I still don't know how you don't have either of these.
Ghouls ‘N Ghosts - A must have.
Altered Beast - Not a stellar game IMO, but still fun.
Afterburner 2 - Not nearly as good as the 32X version, but good enough if you don't have a 32X.
PGA Tour Golf II - Great golf game if you like golf.
World Class Leader Board Golf - Also a decent golf game.
Cliffhanger - Some people think it was crap, for some reason I liked it.
NBA Jam - Another must have.
Steel Empire - What a sleeper. It's a side scrolling shooter, one of my favorites of all time. Nothing about this game sucks. Also a must have.
Robocop Vs. Terminator - What can I say, just buy it.
Outrun - A Sega classic.
The Immortal - Awesome dungeon crawler from EA.
Road Rash - How can you not have Road Rash. This is another Genesis must have.
Road Rash II - Not as good as the first but still very worth owning.
Skitchin - Road Rash on roller blades. This game is also a must have.
Rock N’ Roll Racing - This was an awesome racing game. Cool cars, cool music, and the ability to blow opponents up and upgrade you car.
Super Off Road - Great arcade game port. Simple but a lot of fun.
Virtua Racing - Once again, better on the 32X.