Gauntlet ,chaos engine etc...this is the way

(with NETWORK support ofcourse) 1->4 players
Super Sprint/badlands/dreamcars/indy heat/super offroad remake for WB would have been AWESOME , ofcourse with tcp/ip
Kickstart 1 or 2 ??

A nice tetris one with tcp ip....or what ever, tou i would love a BAM clone if it was great!.
but on the top of the list..... An adventure game
anyway , if you want succes , then port Deluxe galaga to RTG (ppc) ...a sure winner

(or the sequel.... WARBLADE)
good luck!