Hi Becco,
He sounds like a good endo although I don't agree with him on meds being needed for a lifetime. This simply isn't borne out in studies, and Graves' disease is a self-limiting disorder. But I guess you'll be able to show him over time that permanent remission is possible.
It's a good idea to have an ultrasound when a nodule is suspected. A 10 mg starting dose of methimazole for you sounds right.
Best, Elaine