Hi Cooper001,
It was probably an overkill on our part, but here is the list of docs we submitted:
1. Marriage certificate
2. Printed photographs together from last few years
3. Joint apartment leases (probably it would be good to have joint bank accounts and tax returns, but we did not have those), utility bills to the same address, joint cell phone account with a log of very frequent calls
4. Flight itineraries log
5. Evidence that my wife is a benificary on my insurance and vice versa
6. Wedding party pictures and the website/invitation
Good luck!