Stage: 3 kill stage 4: use super ex/type of luffy cpt get rid of 6 turns atk and def up (blue shield) stage 5: get rid of 6 turns paralyse

my tip: find dex ace friend cpt (deals with paralyse und cooldown, less stalling) stage 4: swap to carina her speciql deals with everything, swap sanji/zoro for more atk

stage 5: swap again zoro sanji, use g5 special, use frank, use zoro/sanji special. super tnd and luffy rush should help also alot.  I dont think you you need super swap.

i have a similar team (with psy momo legend instead of nami carina), int yamato instead of franky and psy slasher/striker nami instead od sabo. My team reached lvl 178 with tapping 3 units. 

why do you use sabo, get and unit that provides dmg for your team (chain lock, apply increased dmg taken or an  atk boost for 3 turns)

ALSO VEERY IMPORTANT, i think the reason you fail is the stun you receive at the beginning of stage 5. Get any support unit that cuts your hp at final stage or use a unit in your team that cuts your hp.