I would consider Armour Thyroid. I think it's more natural for medication to include a full range of thyroid hormones. (t1, t2, t3, t4)
I would stick with synthroid (or levoxyl) -- the titration of medication seems slow but depending on your age and heart status, is sometimes necessary. Not typical for the thyroid med to cause a throat ache unless the pill is getting stuck in your throat -- take with a lot of water to prevent this.