What a clever, clever gastro doc! Who'd have thought he would even look at something at the opposite end...
Seriously, that guy is on the ball. A gem in the medical world.
Your endo holds a common view among that speciality, but he's wrong. You clearly have symptoms, and treatment now rather than later can prevent more nodules from forming and the goiter from getting bigger.
The only endo that I saw treats even if TSH is in range, when there are symptoms and antibodies present. She knows that early treatment can do the things I mentioned above. Her position is uncommon among endos, though.
I strongly urge you to find a doctor who will treat you now, before you get even worse. It doesn't have to be an endo; a good family practice DO or MD may be the ticket. If you check Armour Thyroid's physician finder, you may be able to find a more progressive thyroid doc who agrees that early treatment isn't taboo.
With your family history, signs and symptoms, I wouldn't wait. I had to be aggressive about getting treatment myself, so I understand how tough it can be to find a good thyroid doc, but it's truly worth the effort.