What visa benefits do I receive after marrying a Thai national while on a SETV?

how about you come here FIRST and get married. THEN you can worry about the visa you may or may not qualify for based on marriage to a thai. ;)

I'd get at least a single entry tourist visa BEFORE you come here from the thai consulate in your country. Then get here, get the paperwork all done and get married.

IF you meet the financial requirements <- 400K baht in a thai bank account in your name OR a letter from your embassy here stating you get 40K baht a month in income you could get a 90 day Non-O visa from the immigration office and then after that apply for a yearly extension of stay based on marriage.

OR

Once you're married you could go to the thai consulates in Savannakhet Lao or Ho Chi Minh City Vietnam and get a year-long multi-entry Non-O visa based on marriage without needing to show the proof of funds.