1. every jeep is different, but mine ('98 XJ) required me to shim the t-case about 1/2" to get rid of slight driveline vibes. Some say you should use a track bar reloating bracket or adjustable track bar, but I did not.
2. I've run 31s and they did rub in a couple spots. I believe the general concensus is you need at least 3" or some fender trimming to get by with just an OME lift. You'll be more likely to rub when using discos. 30x9,5 or the metric equivalent may be a bettter choice if you aren't going to lift it more. I'm running 255/70/16 which is slightly under 31" in height and about 9.8" wide. My tires will touch in places when flexed out, but not bad enough to damage anything. You may be happier with the smaller tire from a performance standpoint.
3. Sway bar discos are not automatically included with an OME lift. Some vendors assemble parts from different manufacturers and my include one. I've used JKS with good experience in the past, but have not used any other brands.
*'03 Land Rover Discovery HSE, OME susp., ARB Bull Bar, Warn XDi winch with sythetic line, Hella 4000 lights
*'98 Jeep Cherokee, OME suspension and other tweaks. (sold)
*'72 Suzuki LJ20, 1.6VW diesel, sprung over with 33"s and other tweaks.
*'66 Chevy II 2dr hardtop, 23K orig miles, Lowered with rims, otherwise stock 283 powerglide