*Alloy of Law Spoilers!*
After reading Alloy of Law, I was thinking a lot about TLR and what the limit of his powers would be. One need only look as far as Miles to see how much power TLR had at his disposal.
Miles compounding of gold tells us a lot about the nature of compounding Twinborns. When you think about TLR as a Twinborn with every possible combination and being able to compound each available metal, it would seem as if his power was infinite. Gold alone made Miles practically invincible, and it does mention in MB that TLR was completely invincible. (I don't have my books, but I think the quote is something like:) People burned down his inn and he walked out of it growing new skin immediately, and decapitation only annoys him. That seems pretty similar to someone compounding gold.
If TLR was compounding each and every one of his metals, with a little hemalurgy thrown in there somewhere, plus his past as the Sliver, that should explain why he was considered a god.