If you enter Thailand on a Multiple NON-xx Visa, you get a stamp which allows you to stay 90 days, not 365 days. 365 days is the Validity of your Visa not the permitted length of stay.
What did you do after the 90 days? Did you go for a border bounce or do you get extension of stay?
If you get a SETV in London, it should not really be an issue as long as you have Return Ticket within the validity of your stay and funds. They still might question you but don't think it should be an issue.
Maybe a slight issue as you want to stay in the country for more than 60 days, but if your ticket is within the 90 days, you might not have a problem. Down to the immigration officer.
Maybe don't return this year ;-)
Maybe use new Passport although they still see on the screen when and how often you've been in Thailand in the past.
Get married. Slavery isn't to bad with the right girl ;-)