Vacuum damage can't be increased with bonuses. This is despite it having modifiers that show it should. It lacks the red underlined variable in the scene file which kills all dmg possibility of dmg bonus.
Maybe this is deliberate though? In which case, treat this as feedback that it's kinda boring not being able to buff stuff.
(also think it would be very cool if the draw in effect was separate to the dmg effect. having it draw in enemies all the time instead of only when hit.)
(whoever dreamt up the vacuum effect. SSS idea. these kinds of things are amazing to play with. gud job 👍 )