I don't play my 360 much either KDR.
I think if I were to list all of the games I like for the system it would look something like this:
Assassin's Creed
Banjo-Kazooie: Nuts and Bolts
Beautiful Katamari
Crackdown
Earth Defense Force 2017
Guitar Hero II
Kameo: Elements of Power
Ninja Gaiden II
Saints Row
Table Tennis (only fun with other people)
Viva Pinata
I know you've already confirmed that you've played or can't play some of those; however, three that I didn't see that stand out are Assassin's Creed, Banjo-Kazooie: Nuts and Bolts, and Kameo: Elements of Power.
Depending heavily on pricepoints, those games are definitely worthy. Kameo is super cheap around here, and as such I felt it was well worth all $15 I paid for it. Banjo-Kazooie is nothing like the original titles but if you enjoy building stuff (like Legos, K'nex, Erector Sets) you will definitely connect with the game. As for Assassin's Creed, if you don't mind a bit of repetition and enjoy aimlessly exploring huge cities, the game is highly enjoyable. I find myself playing it from time to time to enjoy the landscapes and find hidden flags in the vast countryside and cityscapes of the game.