Starflight friggin rocks...definitely one of the best of the era, and probably the best on the Genesis.

I have to say that Super Metroid and Chrono Trigger were also some of the best of that era, and two more of my favs. I also must mention MUSHA, Space Megaforce, and Blazing Lazers, for that matter), as being top notch shooters. The best platformer, I'm going to say Sonic 3 & Knuckles locked on, because together, they made a fantastic game.

Overall I'd say the best go like this, for me:

1. Starflight
2. Chrono Trigger
3. Sonic 3 & Knuckles
4. Super Metroid
5. MUSHA