I agree. Not necessarily too old for a male to marry the first time but unusual for a female. If that is your James Suit (father of Ann) on the 1800-10 St. Mary's County censuses, he still had younger children at home, didn't he? I didn't copy it but there were children in the household. Seems a Suit b.1762 would be more his peer than his child. I read some of the other posts on this and the "Suit" board and seems there are a number of generational mixups. But I haven't researched the Suits so cannot honestly say. There are a number of Herberts in St. Mary's County and if James lived there then it seems more likely his daughter married there, don't you think? There are three different Nathaniel Suit estates in P.G. County in far different years so they can't all be the same.
If there are several differing opinions, it's best to just stick with what you have documentation for and work your way back step by step. That way you'll know for sure and be satisfied that it's correct.
Good luck! And thanks again for taking the time to post a reply to my query.