I don't know if you've read the silmarillion, but you could even compare morgoth to ruin. I guess that would make manwe preservation, if you want to go that far...?
you could contrast Vin with Frodo. They're the heroes of their stories, but they have vastly different backgrounds and personalities and are affected by their responsibilities and duties in different ways.. though they do both have a best friend that sticks with them to the end and ends up being vital to their success (vin/elend, frodo/sam)
Ooh, the fellowship is kind of comparable to Kelsier's crew. And eowyn is a total boss, just like Vin. c:
Plot-wise, though, both occur over the course of three books and end in overall success, though the main hero(es) were required to sacrifice a TON for their goals; although, in my opinion, Frodo did so more than Vin. In both, there were multiple people whose roles were vital to the success of the mission. Frodo and Sam's role involved being as inconspicuous as possible, while Vin and Elend's duties required them to kind of take the spotlight and lead everybody.
Both TLR and Sauron are unseen for the majority of the books they're a part of. The reader knows about them mostly through reputation and information given by the characters.
this might not help and it's a bit, but hey these are two of my favorite series. I had to :B