What are the best passport options and visa application procedures for moving to Bangkok with family?

If not already done, and depending upon where you were married, you may be further advantaged in the future, to have your marriage registered at the Amphoe where you are registered in the Tabian Baan. And possibly have your name changed from your original Thai family name to the same family name in your UK passport. You can then get a Thai ID card and passport in your new family name.

Why not use your nationality to enter your nation? I don't see any bright side on you entering Thailand on a UK passport unless you have a very specific reason to have to be a UK citizen in Thailand.

You are considered as the nationality of the passport you enter Thailand on.

You can change your passport between the countries (international travel) without any problem as long as you are flying (not at the land border). You leave the UK on your UK passport and enter Thailand with a Thai passport is no problem at all.

If your husband wants to apply for Non-O being married to a Thai (you), you have to be a Thai in Thailand.

When your husband applies is totally up to you.

Non-O from UK: your husband needs to open a Thai Bank account immediately, transfer money, season his Funds for two months, then apply for a 1-year extension within 90days from entering Thailand.

Non-O in Thailand: he enters Thailand on Tourist Visa (60days on entry) or visa-exempt (30days on entry), opens a Thai Bank account, transfers money, then applies for a Non-O in-country visa while he has 15days (21days in CM) or more with his stamp. Funds don't have to be seasoned. He can apply for a 30days tourism extension once if he needs more time. Then when his Non-O stamp is less than 30days (45days in Bangkok, CM, etc) he will apply for a 1-year extension. This time his funds have to be in the Bank for two months.

Anyway, you need to prepare enough documents including marriage, birth cert, for your Non-O visa/extension application in Thailand.