It's disappointing how so many game devs these days think that 'difficult' simply means 'overtuned enemies, undertuned players'.
Enemies are not overturned in Tactician Mode, if anything they die way too fast as the game progresses. The problem is the non hand holding nature of the quests that messes up with a lot of players.
Act2 for example, a lot player run straight up north where they would encounter level 13,14 enemies when they are only level 9 or 10. They would die a lot and complain the game is too hard. If they talk to everyone in town, quests should take them west level 10-11 area, or east level 11-12 area, then further east level 12-13, then northwest level 13-14, northeast level 14-15. You will have no problem killing anything if you follow these directions. You will probably over leveled if you do every quests and everything will become very easy because gear stats doubled every 2 levels.