in all honesty and my opinion, its doesnt matter if you have the xe or se. some have leather seats, some dont. some have 6 cd changers, some dont. some are supercharged, most arent. the only 2nd gens have trim levels to pay attention too because of the factory e locker in the offroad/pro4x models.
as for maintenance, make sure you get your timing belt replaced if it hasnt been already. 100k-110k is when they got to get changed. as for mods, brower the build thread section
here and browse threw some builds. there is really only few ways to build first gen Xterras.
welcome to the club, dont forget youre here forever.