I've only seen like two episodes of the new avatar. And so far I like the first one more. I don't really have an opinion on the new one yet though.

We'll I've seen all the l.o.k episodes so far and have watched the full avatar show several times over. In my opinion the first outweighs the second in every regard except animation (but that isn't a credential, it should be that way regardless).

Some points:

-The second show plays heavily to Korra's sexual development in terms of drama surrounding "boys" she may or may not be attracted to (much more than Avatar that focused on story development regarding the four nations and Aang's bending training [with a side-story involving Aang's affections for Katara]). In the new show (so far anyway), Korra's affections dominate the show (only the first episode was spared the "drama" and it may have been introduced at the end actually...)

-The first show involved several characters as protagonists (starting the show with Sokka and his sister Katara) and lending time to even the antagonist Zuko who develops into more of an anti-hero as the show progresses, whereas the second show focuses solely on Korra and her development. The antagonist (so far) is flat ensuring that Korra will be the main focus of this show hence her adventures with boys and bending will be at the forefront until new characters are introduced (if ever).

-The comedic value of the first show was apparent from the first few seconds to the very end, calling upon several (Aang, Sokka, Toph, Zuko, Iro, Katara, Appa and the list goes on) characters, whereas the second show relies heavily on one character (goofy dude that likes Korra [don't know his name]) and even more numbingly on "awkward" exchanges between members of this love traigle comprising Korra and two "pro-bending" brothers (goofy dude that likes Korra and his brother that acts as though he doesn't). The one saving grace that keeps my hope alive is that this show retains the first's writers, potentially building the show into something as amazing as the first. One scene made me lol in the second show (first episode) when a little airbender was gnawing on his grandfathers head as they landed an air bison - whereas I found myself at least chukling on a semi-regular basis with the first.

More to come if necessary, and I welcome a critique from someone favoring the second.