Congrats bro!
All weather floor mats are essential for kids/outdoors. They have saved my ass more than I can count. Weathertech is what I have.
Read up on HID's.. There are a few people that regret it, read the "bad idea mod" thread. The stock headlights are really wide and provide a good visual. maybe add some led fog lights instead (rigids) ??
IF thats in your near future, make sure to pick up some OEM switches right now , group buy!! lol
Regarding your leveling question, use this in the search box and type what your looking for after 'site://toyota-4runner.org/5th-gen-t4rs'
such as site://toyota-4runner.org/5th-gen-t4rs Leveling front. It's one of the stickies as "alternate search".. I don't blame you, because it took me maybe a year to realize it was there lol.
Have fun!!