i havent encountered the same problem but i do understand not wanting to redo an entire dialogue because you lost a fight. Id recommend to save right before entering a battle
(which i know you usually cant cus the battles are sprung on you but u can still do it on the second try)
As for the battles taking you hours idk what to say i havent encountered that problem the battles usually take like 10 minutes and it takes 2 tries for the hard ones.
edit: id like to add that im getting a delay on when to turn starts and when i can select cards of like 20 seconds and its really annoying