3 choice maps to use

I’ve been doing alright the two weeks I’ve been playing this game. Pictured is the current iteration of my team that carried me to a decent rank. I feel like I need a decent defensive unit that can take hits. Thinking of swapping out millennium Godzilla. I have 3 choice maps from a rank promotion pack and am thinking of investing them all into GMK Godzilla (who I already have a level 1 of) or Kiryu Kai (who would be new). Any tips are greatly appreciated.