Bull bar and LED bulbs are strict no no from RTA passing point of view. LED bar is also no but you can get away by getting it removable cover.
Tires life depends of tire tread offered by the manufacturer. Every tire is different and some last for 20-30k (Dunlop / Bridgestone) and other goes up to 60k (Michelin).
I had BFG in my Patrol and they def look awesome but they are very heavy and very noisy. I definitely do not recommend them, unless you have serious engine mod as they restrict your off-road climb capabilities to a greater extent. Also, you need a very loud sound system or noise canceling headphone to counter the tire noise (I'm serious). I have done a couple of Liwa with 3+ hour road drive and I went almost deaf after that and kept on hearing humming for few hours. Heavy tires will also sip extra fuel.
Instead, you can go for Yokohama Geolander A/T having nice moderately aggressive tread that looks good and offers AWESOME off-road (Sand + Rock) performance and just produces tad extra noise than highway tread, which is acceptable. I'm using them for 5 years and changed to the second set of same tires last year. Many regular off-roaders have opted for same and you can verify that by checking the majority of FJC, Xterra, Cruisers, Patrols and Pajero running with them now even more than before.
Spacers are a good add-on for increasing the stability if you have a too high lift but just make sure you go with a good branded one and not fake / cheap ones as they wobble and impossible to balance correctly.