I use a modular system by use of a carabiner. Take off what I need, leave the rest somewhere accessible (like a backpack, glovebox, desk drawer, nightstand).
The modules on it are:
1) Motorcycle, Garage, Yard Gate
2) My house, crawlspace, shed
3) Parents house indoor & outdoor
4) Car + a ~dozen keychain consumer cards
5) Work keys + 2 factor id token
6) Karate Dojo key, bicycle lock
7) Parent's vehicle
I usually dont need more than 2 pairs of keys at a time, (vehicle and destination). Its not perfect, but I'm not sure whats more annoying, not having a key when I need it, or having a huge bulge in my pocket stab me in the leg constantly. Its still not as annoying as my girlfriend's
yawara/Kubotan keychain ...