Osaka Castle

Finally made it to floor 95! I wanted to reach floor 99, but the enemies got even stronger from floor 96 onwards. Even with Hakusan in the party, everyone keeps getting heavily injured and I can't progress... I don't have many talismans either, so I guess it's impossible to go further with my current level. Should I give up and go back to around floor 80 to level up and earn some coins?