Good choices, but again, mostly ones that blend beat 'em up with other genres. Is that the only way beat 'em ups work now?
I don't think developers know how to make a pure beat 'em up game anymore. It's incredibly hard to make a long game with gameplay elements that get repetitive quickly. If they don't blend RPG, puzzle, or other genre elements, the game starts to get really tiring. Consumers were a lot more accepting of games like Streets of Rage back in the 1990's because games weren't particularly long. Games have evolved and I don't think players would be accepting of such simplistic games anymore unless it's something constantly fun like Mario. I think a good example of this is the Golden Axe game that was made fore the 360 a couple years back which was hated by everyone.