Interesting. I wouldn't argue that Frodo and the Fellowship are examples of absolute good. Boromir was corrupted by the ring and tried to forcibly take it from Frodo. Frodo ultimately gave in to the temptation of the ring and refused to destroy it, claiming for himself. It was only destroyed by accident when two characters who had been corrupted by it were trying to kill each other over it.
LOTR is not about pure good triumphing over pure evil (Frodo failed to withstand the temptation of the ring), it's about evil destroying itself. The forces of good were not going to prevail at the Black Gate--they were going to be slaughtered. Gandalf and Aragorn didn't triumph over evil in the climax of ROTK. They got lucky. Frodo didn't triumph over evil, he was corrupted by it. We only got a happy ending because the evil of the ring accidentally caused its own destruction.
LOTR is not the simple good vs. evil story some seem to think it is. Other characters like Saruman, Wormtongue and Denethor are not pure evil, they are good people led astray because of their faults and flaws and temptations. LOTR shows that absolute power corrupts absolutely, a theme that it probably has in common with GoT. Characters in both series exhibit a mix of good and bad--it's not all strictly black and white. GoT certainly has even more shades of grey in its large cast of characters, but LOTR is not as simplistic as some are painting it to be.
At any rate, I certainly can't call GoT better when it isn't finished yet. I'm not going to vote when one of the two choices is a work in progress.
Once all the petty political bickering and selfishness and betrayal has played out, we will still be left with a major conflict with the White Walkers. I think they are going to be pretty purely villainous and evil. No shades of grey or sympathy. Just like LOTR, GoT has some pure evil to contend with, we're just getting distracted by the other stuff first. Just like we saw happening in Rohan and Gondor, there are very human issues distracting the kings and rulers from the larger threat looming in the background. Both series ultimately have a supernatural pure evil that is going to need to be vanquished by flawed characters. In LOTR, the heroes ultimately fall short. We'll have to see what happens with GoT.