Among the modders eagerly tinkering away at Fallout: New Vegas, arguably "correcting" what they see as deficiencies in the original design, is ... lead designer J.E. Sawyer. Sawyer has developed an optional patch for the PC version, which reduces the level cap to 35, halves XP acquisition, cuts water and food drop rates, and tweaks a bunch of other variables, all detailed on Sawyer's Formspring. You can download the mod here.

So why is this a mod instead of an official patch? "In addition to technical reasons," Sawyer said, "some of the mechanics changes make the game significantly more difficult (base health / stim changes) or at least more of a hassle (carry weight, stims having weight, H2O/SLP/FOD rate increase). I'd rather have people opt-in to those changes than make them the default in a patch." This is also something Sawyer is doing in his spare time, as nobody is officially working on New Vegas anymore.