There's plenty of good, cheap, U.S. multiplayers so I'll stick to those. Actually, I honesty don't think you can really go wrong with any U.S. multi-player title.
I would just mix up your genres a bit. Since you already have Bomberman, maybe wait on Battle Load Runner because it's so similar (it is totally great though).
Shooters: Ordyne, Areoblasters, Monster Lair.
Sports/Brawlers: Battle Royale (5 players), Hit the Ice, Power Golf, and World Sports Competition (5 players) are all light on the rules and easy to learn.
Closest things to U.S. beat-em-ups: Cadash, Shockman.
Platformers: Buster Bros, Parasol Stars, Bonk 3.
Puzzle/thinking: Chew Man Fu, Splash Lake, Klax, King of Casino (seriously makes me what to gamble).
RPG (besides DE2): Double Dungeons!
Racing: Final Lap Twin, MotoRoader (5 players)
Modify your TurboTap here!:
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