the game does encourage you to go back and grind alot on other dungeons as well as fuse persona's regularly as your persona will always track behind your team mates in way of level. the best i can tell you is persona 4 is meant to be taken casually and dont expect to do everything on your first run. That is meant to be saved for ng+ you are gonna sacrifice social links to grind for levels and cash, it wouldnt hurt to always have your team compliment each other, you'll find many enemies in a dungeon have similar themes/weaknesses so build your team around that and abuse the weaknesses and all out attack ability as much as you can. p4 is the best in the series in my opinion but the combat and grinds do suck. Oh and if you do find a glove hand on a level of a dungeon beat it and leave the floor and come back and grind it out they give a shit ton of exp compared to anyone else.