What can I say? I'm ALSO a sucker for the Sword ability. Ok but this is how much I like to see/ use the ability, not how effective they are, although that's one of the biggest factors.
I would say the best ability evolutions, in order, for practical in-game use, like combat, are: 1 Morpho Knight sword high damage, absurdly good dodge, life steal (heal yourself when you do damage) on multi-hits, and a lot of great moves. 2 Meta knight sword the upper calibur attack is op and stunlocks bosses for huge damage. 3 masked hammer High damage and good reward off a roll. also homing tornadoes.