Not rare per se but I'm honestly thinking of axing my TG-16 wishlist items because once I pickup Bonk and Bonk's Revenge I don't think I can afford anything else worth getting on the console.
Looking at your TG-16 collection, I can recommend you some affordable TG-16 titles worth checking out:
-Blazing Lazers - Great shoot-em up with nice big, chunky sprites.
-Bloody Wolf - Great combination of Contra & Ikari Warriors and easily one of my favorite games on the system.
-Bonk's Adventure - This game is almost no-brainer if you own a TG-16.
-Dragon Spirit - Great vertical-scrolling shoot-em up with a fantasy flair where you control a dragon. Much better than the NES version.
-Legendary Axe - A good action-platformer.
-Ninja Spirit - Very fun, and overlooked action-platformer with some impressive graphics that really shows off the system.
-Turrican - Great run-n-game in the Contra vein.
-Victory Run - It's a Rad Racer/Outrun clone. But it's a very nice looking one. So if you like those type of racing games, this is worth getting. Especially since you can find it for under $10, easily.