I've tried to limit my collecting to:
A) Hard Rock (chips, tokens, pins, slot cards...
B) One from each LV casino (open or closed)

My preference for item B) is $5 chips, but if all I can afford at the time is a $1 chip opr if it's the only one available, I get it & try to upgrade later.

And I collect certain metal/coin inlays, too. OOOOOOhhhh, shiney....