I'll mainly be on light trails, nothing too rough, and plan on going with a 30" tire with spacers (1"?) and stock rims as I believe people are saying that a 31" will rub occasionally.
I'd go with a 245/74R16 tire. If you want added backspacing and plan to use stock rims, look into hub-centric bolt on spacers. Rough Country has them in 1.5" and SpiderTrax has them in 1.25".
With 1.5" spacers and 245/75R16 tires on a 3" lift, you'll have very minimal trimming, if any, on the lower portion of the front fascia.
Here is my question: Are there any parts in addition to the lift kit itself that I should automatically plan on installing in order to avoid death wobble, preserve halfway decent ride, etc?
I would upgrade to an adjustable track bar, upgrade to Bilstein shocks, add in a heavy duty steering stabilizer (Moog Super Trail Boss - SSD107), and add on new spring isolators. Another additional item some prefer is the Addco rear sway bar. It is supposed to help with cornering tremendously but will limit your flex off road.
(All of the above, including the IRO 3" lift, can be purchased through forum vendor Kolak.)
Per avoiding death wobble, check the condition of your tie rod ends and control arm bushings. If they are worn, you may consider replacing.
Are the IRO bushings good?
I can't comment on the bushings as I have not ran that lift. Many people are happy with it though.
Do I need to double up the steering stabilizer, and if so what's recommended?
No. Dual stabilizers on the WJ actually add more strain to the steering system.
Will my present CV-style front prop shaft work or should I budget in a conversion shaft?
It may work. It may not. Consider saving a little for this in the event that it fails.
Should I skip the IRO lift, and if so, what's a better alternative? What extra plans and purchases should I make/budget if I choose that alternative?
IRO is a great choice.