Hm? The bat or the spear?

Schizofrangelo Hamatovich: Which weapon would you be more handy with? The bat or the Supreme Guardian's Spear?

The spear allows you to become a shield for your allies, a support, but you can't really do much with it unlike the bat, which allows you to inflict unimaginable damage to the enemy, but then defense is out of the question...

What I'm going to choose between a bat and a spear is the one that deals more damage overall, so why choose one when you can take both and hit someone's mug with an Ultimate?