My choice would be to wait until I'm in country, then do it. That said, it is still important to determine the issues and rules based upon your home country.
A part of what we see with Imm paper work is to help more Thais have jobs. Thailand goes out of their way to create as many jobs for their citizens as possible.
Just did my first boarder bounce in many years, got 60 days - BUT - big surprise to me, the boarder bounce now must include "1 sleep" across the boarder; next morning, you're on your way. Comment was made by senior immigration guy - that is a Cambodia 'requirement'; looks as if Thailand may stop the "1 sleep" in the future and just do the old time "boarder bounce".
In the US, your copy of the marriage certificate is probably certified. Also, with a Spouse visa, you will quickly learn to compile a 'Spouse renewal' file folder. Makes annual renewal of husbands extension 100 times easier for the Thai wife. Keeps all the documents, copies, pics, hand drawn maps, and related stuff in one place.
Depends on your home Province and district. May require an official Thai translation (meaning notarized); the folks who do the official translation can provide the notary. Then register your marriage in your home district office; will need to provide current updates of active marriage from local district for O-spouse renewal of extension.