Ultra Sword would seem more likely. it would take up a huge chunk of the stage and has great knockback and damage.
Ultra flame just seems like a mario fs clone,
Ultra beam just seems like a pikachu fs clone
Ultra snowball seems a little wierd and awkward to control.
Grand Hammer i really like. on start up, if you press A in time with the growing hammer, you can get up to a 3 tiered hammer that greatly increases its size, damage, knockback, and shockwaves. if you miss time it, it does the 1 tiered hammer or a 2 tiered hammer. <-------- this along with ultra sword seems really hard to dodge.
i like the idea of mike kirby, seems like DK's fs but more linear, kinda like wft fs right now.
Crash kirby would be da bomb.... literally. i giant explosion similar to a smart bomb, or that one pic on the 3ds sakurai showed to us.