Bathroom Emergency Baskets: basic meds, band aids, mini sewing kits, safety pins, bobby pins, hair spray, spray on deodorant, hand lotion, clear nail polish, white chalk, mouth wash, mini flossers, lady needs, antibacterial hand gel, fashion tape, nail file, Tide marker, tweezers
A lot of things we likely already have and would just need to throw in a basket.
Individual Wedding Survival Kits: mini flosser, 2 starlight mints, handy wipes, kleenex
If the venue doesn't provide it, put nice hand soap in the restrooms (like the soap/lotion sets available from Ross/Marshalls/Bath&Body Works)
Provide safe ride home phone numbers and mints at the exit.