first you used an improper filing status. single is not available if you are married at year-end even to an NRA.
the only proper filing status was either married filing separately or head of household if you had a qualifying dependent (not your spouse) with either an ITIN or SSN. for open years you can amend to MFJ. (2017 if extended you have until 10/15/2021 otherwise you are too late) for closed years if using with MFS or HOH, if qualified, the IRS can come after you if you would owe taxes using that filing status.
as to married filing jointly
it will subject your spouse’s entire income to U.S. taxation and possibly subject your spouse to other informational reporting requirements. if applicable, FBAR and Form 8938 filing are required if you file MFJ (there can be substantial penalties for filing late). Practically speaking, this status is most beneficial if your spouse does not earn any income or otherwise have any accounts or investments that may cause negative tax consequences from the U.S. side.
you may want to consult with a tax professional.
