other than the obvious stuff like rings, charms, uniques.. i pick up:

whites that could be good bases (mage plate, tmaul, cv, ca, thresher, gt, etc)
blues that are armors, antlers, barb helms, javelins
all hell level rares

am i missing anything? should i be picking up normal/nm level gear too like rare crystal swords? (i usually farm hell chaos or tz)

rare crystal swords you pick em up if they are eth, hoping they get cruel/ias/fools and such to upgrade to PB -> no need eRep
same goes with DB

eth rares globally, apart from CS/DB you'll be looking for eRep (altho few items can do without), there are some bases that will sell way easier than others, like Ancient Armors for LLD.

going to the sticky about which LLD items to pickup can be a good start to ensure you're not charsi'ing good stuff.
https://forums.d2jsp.org/topic.php?t=14161522
https://forums.d2jsp.org/topic.php?t=41050073&f=123

also, picking up all elite items is more of a waste of time than ensuring value, as some items will never sell (or there will be 1 buyer in 5 years for a supra specific item)

trophy room gives a good view of what can be considered really good and valuable aswell (the real trophy posts ofc) and may widden your pickup pool a bit.

2nd job and just buy the items u want