I have a TG-16, nice system with some great games. But Keith Courage is not one of those great games. It's strange, and it's cool to play through for that reason. But it's not gonna win any awards for the greatest platformer.
My TG-16 broke a couple years back. My fat-ass cat sat on the controller right where it plugs into the port, and broke the controller port, rendering the console useless. Never thought I'd come across one again at a decent price considering the retro-craze, so I sold all my games.
My awesome wife re-brought one for me just last year, after hearing me hold a grudge against the cat for a couple years. Since then I've only re-bought about 3 games for it, so I have a ways to go on getting my colleciton back.
As for the greatest systems of the 80s and 90s, come on now Slothing. You can't be serious, are you? With competition like the Commodore 64, NES, SNES, Genesis, and PS1; you can seriously say that? It's a good system, but not the best of the 80s and 90s.
Some recommendations, if you get one:
Action:
-Bloody Wolf
-Dungeon Explorer (fun little Gauntlet clone)
-Neutopia 1 & 2 (very well-made Zelda clones)
-Ninja Spirit
-Space Harrier
-Splatterhouse (slasher-themed action game)
Platformers:
-Bonk's Adventure
-Bonk's Revenge
-Legend of Hero Tonma
-New Adventure Island
Shoot-Em Ups: (This is the reason to own a TG-16, if you're a shoot-em up fan, a ton of great shmups on here)
-Blazing Lazers
-Dragon Spirit
-Lords of Thunder (this one is actually a CD-attachment game, but IMO, the best shoot-em up EVER. Such an awesome metal-themed rocking soundtrack on this one. I got to play it via Wii's virtual console, well worth the download.)
-R-Type
-Raiden
-Sidearms
-Super Star Soldier
Other:
-Alien Crush (very fun, and unique-looking, video pinball game)
-Cadash (an arcade action-RPG, as strange as that may sound, pretty short game, but fun)
-Victory Run (Rad Racer/Outrun clone)
I never did have the CD-attachment, so I never got to play some of the more well-known ones like Fighting Street (Street Fighter 1), Castlevania: Rondo of Blood or the later Ys titles.