I've never had problem with ruts as the narrower Samurai track allows me to drive between the ruts caused by the larger jeep & trucks.
Again, when you go to 33" tires, you've got to upgrade a lot of components. Bigger is not better. (The Samurai that I have with 33" tires has the old Spidertrax Sidewinders (look like their Spider 9s) which had a rear 3rd from a Sidekick as a diff, Dana 44 joints, Full Floater Rear and discs all around. Pretty beefy for a Samurai. I don't think I would run 33" tires on a stock Samurai axle.)
I tried the 4-door Sidekick rotors, but I could never get them bled completely. Tried it numerous times (grinding and refitting my OTT steering arms) and finally gave up and went back to the original brakes. If you swap your front discs to the back, then you will have no emergency brake. Yes, TT sell a kit that has an emergency brake, but you don't get full pad life as they must be replaced around 50% wear.
Also, I've got the front end "stretched" 1-inch via the centering hole mod and I'm just running stock front leafs. I get a little bit of rub in the front during full compress but it isn't too bad. I have bumpstops setup for about 2" of uptravel too. I did have RUF at one point, but I went back to the stock fronts for better axle placement in the wheel well. The Samurai with 32" tires/SPOA is pictured below. This was on Hell's Revenge, 2011 Zukfari.