Flad landers, sheesh.
Posi lock indicates that your wheeling will be at least serious enough that you can't afford to not have 4x. How into jeeps and jeeping a given person is, is how I answer this question.
If you are sold on the virtues of jeeps and wheeling, 35" tires are next with lockers an axle swaps not far behind.

4.56 or even 4.88 is just fine with 33s assuming a 5 speed
manual tranny, if automatic 4.10 or 4.56.

Forget 3.73.
You have mountains to drive, snow to wheel (snow we have here now 24") get gears that not only suit the imediate need but future needs as well.