How long should I stay in Laos before returning to Thailand on a tourist visa?

Read somewhere it is taking a week or more to get a visa at the thai consulate

I would visit travel-pilot.com and check “visas” section and ask Captain Charlie your particular situation for advice

Russell needs his Swedish marriage documents legalized by the Thai Embassy Stockholm.

He can apply by the e-visa system to a 90-days Non-Imm-O Family Visa, using the original Swedish marriage documents.

He however cannot use these for applying for anything inside Thailand, and he cannot use them for an application to the visa in any country outside of Thailand, EXCEPT in Sweden.

He enters Thailand on a 90-days Non-Imm-O Family Visa, and then get the Thai embassy legalized documents “co-legalized” by the MfA in Bangkok.

After this he can get the marriage registered on any Amphur office.

This is the ONLY way to get his marriage centrally registered inside Thailand.

For the application to the 1-year extension of stay on Immigration, he needs to show a freshly printout of the Kor Ror 22 or 2 (whichever applies) from the local Amphur.

Even an old Kor Ror 3 rose bordered marriage certificate alone is not enough a proof on Immigration, to show that the marriage is still upheld and existing

Next year?

What went wrong with registering your Thai marriage? If you have the marriage certificate it might be worth applying for the 90 day Non-O visa in Laos assuming you can sort whatever is wrong in 90 days

It depends on your recent history of travel in Thailand..

And of course you are always at the discretion of the Immigration officer you are dealing with on the day..

You should have an exit ticket out of Thailand within 60 days and also the 20,000 Thai Baht cash or foreign currency equivalent in case you are asked..

I would stay minimum 3 nights in Laos or use a visa run agency

Did you really pay for a tourist visa? Your chances of an easy re-entry depends upon your visa exempt entry history for the last 12 to 18 months.