Right Now - A long stay Visa open to Western Farangs that has a realistic chance of being issued (along with the COE) is the Non Imm O-A Visa One Year.
Requirements: MMust be age 50 or over. Must be issued in one's home country at a Thai Consulate / Embassy.
Must have a 800,000 Baht EQUIVALENT in the home country bank for 3 months orior to App. Or proof of a 65K Baht Equivalent income per month x 12 month, plus have a medical cert. plus a Police Background Check Cert. and health insurance + now Covid Insurance. plus Quarantine. A real Snap Huh?
Some Thai Immigration Offices (but by far not all) are authorized to issue a Non Imm O 90 day Visa in a package to be followed up within the 90 days by application for a One Year Extension of Stay based on Retirement (age 50 and over). They may also do this for Marriage also (but not as often. Examples of Immigration Offices that are authorized to do this are CW, CM and Krabi.
Current Covid restrictions have caused the issuance of the Non Imm O Visa 90 days by Consulates / Embassies to be paused. But prior to Covid the Non Imm O was issued routinely for 90 days at Thai Consulates and Embassies. In recent years the Non Imm O 90 day Visa has been frequently issued for Marriage to be converted to a one year Extension of Stay at Thai Immigration. Same with those age 50 and over being issued a Non Imm O 90 day Visa at a Consulate / Embassy for purpose of applying for a one year Extension of Stay based on Retirement.