I just beat the game, going through the main quest as quickly as I could. I was at level 26 after finishing Who Dares Wins, but I have yet to tackle the majority of the side quests, find the rest of the bobbleheads, explore the rest of the wasteland, find the majority of the skill books, and take on the Pitt and Point Lookout. I beat the main quest quicker than I usually do to restrict the number of bullet sponge enemies I encountered, including Super Mutant Overlords, Feral Ghoul Reavers, Aliens with the forcefield, and Albino Radscorpions. The only sidequests I finished were Wasteland Survival Guide, Power of the Atom, Trouble on the Homefront, Those, and Stealing Independence. All this on Normal difficulty.

What I hate about this game is that there is just too much experience gained during only a very small portion of the game. It's easy to reach the level cap before you even come close to seeing the whole game. And if you level up too fast, you'll trigger the appearance of those bullet sponge enemies quicker. The system is too unbalanced.

Other than reducing the difficulty to Very Easy, which would reduce the challenge of the game, is there a way to slow down levelling up so that the game is more balanced? What's the best mod for handling this?