I think I feel good about the amount of evidence we sent. We have a birth certificate for our son born last year, 3 years of joint tax returns, home and auto insurance policies, a house deed and car deed with both our names, statements from a joint checking account, my benefits info from work showing her (and now son) as plan members, as well as a fair amount of pictures and a few affidavit letters. I also think we covered the time period pretty well - for the first year we were married she wasn't in the US yet, but we have pictures (including wedding pics) and plane tickets from that time. Then for '20-'23 we have the more "official" stuff I just mentioned.
I know it takes a while to get a decision but man, that's crazy it can take that long just to acknowledge receipt. I guess we just buckle down for a nerve-wracking wait then.