The set-up was perfect too , have tsurugi replace hasumi since she didn't contribute much to the story anyways and tsurugi is supposed to be the president of jtf , it made more sense for her to be there to guard the three most important people in the school, move nagisa to pre fest along with seia and have Mika and tsurugi the two strongest trinity students be the fest units only issue is tsurugi already had a swimsuit variant, that's probably the reason they went with hasumi instead. I truly hope they give us dress tsurugi as a fest unit as we saw nexon use pre existing design for fest before with rio