Re: nodules and hurthle cell=surgery!
I think the key is that your thyroid levels are well managed---that's what will effect your weight.
I too, think that it's sometimes good to get the whole thyroid out---because even if benign, whatever it is that caused the first nodule to grow, may cause one to grow on the remaining side. It can also help you avoid a second surgery.
I would tell the surgeon--"take as much out as you safely can..." because if he goes in and finds a very diseased thyroid, maybe he'll be inclined to just removing it---you never know how it will effect his decision process during the surgery. Do you have any other surgeons you can use?
You sometimes need meds with partial and sometimes you don't. I have a feeling with your history of family members with nodules, you have an undiagnosed thyroid problem, and probably have needed thyroid meds all along. Sometimes it's good to start with no thyroid, and find a good balance of meds. that way. You really need a good doctor to work with to manage thyroid levels.
My surgery was a breeze---I had thyroid cancer, and had to go through the steps to eradicate it, but now I'm fine. I hope all goes easy for you too!