The Geonosian Warrior Force Pike wouldn't really be any more useful than the vibroblade, but the MagnaGuard electrostaff would be nice to have for its electricity for stunning SBD's and then beating the crap out of them.
It would have been nice to have vehicles in MP like with Jedi Academy. With all the nice vehicles in the Clone Wars, it's sorta a shame they're not applied to the game. You could get with some buddies in a Republic Gunship or an AT-TE, or control Dwarf and Homing Spider Droids or fly a Geonosian Starfighter as the Separatists. Then there's the all-new RotS craft.
*Some Episode III spoilers ahead*
Get with three buddies in an ARC-170 or fly solo in a V-Wing, and for the Separatists, the Vulture Droids and Tri-Fighters, equipped with AI-controlled Buzz Droids and all. Crab Droids, Tank Droids, AT-AP's, AT-RT's, BARC Speeders, Juggernauts... so many awesome vehicles here that could be put into service!