as for interior lights, check out precisionled.com.
Jeep Grand Cherokee LED Interior Package (2011-Present)
this is their standard LED interior kit. ive heard from others on here that the premium is no different. they offer a selection of colors (cool white, bright white, emerald green, dark blue, and ruby red). they have an install video posted on this page, the only tough part would be doing the trunk lights. im wanting to do this but hesitant because im afraid to take off the whole trunk trim panel(i have an altitude as well as my first car and im afraid to be the 16 year old dumb*** that ruins who knows what in the trunk panel). however, seems rather easy to do the whole thing, and you can even mix and match some of the lights (glove box, vanity mirror) for example im thinking about doing a red base for the maps, footwells, domes, and trunk and then white for glove blox/vanity mirror cause itd have a cool red white and blue 'merica theme goin lol.
as for headlights, im just as confused as you are. everything ive read contradicts other posts and have no idea what to do. xenon depot is well rated however and im sure if you give them a call they could help you out.
also would suggest doing black lug nuts/locks on the rims, and the black grille inserts. anyways good luck with your led and headlight situation, and post some pics/feedback if you end up following through with this!