For those who think the politics involving the races in this arc is useless to the overall plot or whatsoever, I have to say your analysis are mediocre and shallow at best.
We should look at the overall picture of the arc and not just focus on the "rescue Asuna" plot-line.
Let's me clarify a couple of things first.
1. What is Kirito doing in ALO?
- Obviously, to check and see if the rumors are correct and if the person in the picture is Asuna.
2. What does Kirito know of ALO?
- Nothing whatsoever. He is a total newbie to the world.
So this leads us to question 3 which is:
- How can a newbie deal with this problem?
The most viable answer therefore is to gather more information on the world.
So how can a total newbie do that?
Just asking questions to random strangers isn't really the most effective way of gathering info in ALO (or any other MMORPGs. Any MMO players can attest to that). It is more effective to befriend a veteran and gather info after instead.
So Kirito befriends Leafa and therefore, has now access to her vast knowledge and experience in the world of ALO plus gaining a friend.
Now, what do we know about Kirito? What are views, beliefs and ideals concerning VRMMOs. What are his experiences regarding it? Everything was answered in the SAO arc.
We already know by now that Kirito cannot and will not betray his friends nor abandon them in their time of need. We already know Kirito is one show boating hero as was shown in the SAO side-stories.
Leafa, now considered as Kirito's friend, is now in trouble. A race war is brewing and Leafa's being suckered into it because it concerns her race and the power balance of ALO will shift to the Salamanders if it was allowed to happen.
Although she didn't ask for Kirito's help, we already know what Kirito will do right? Help her of course.
Now you ask "what's this got to do with rescuing Asuna?"
Let me clarify that for you. What do we know about the World Tree quest? We know that it is:
1. Nobody has every cleared it in the few years of ALO being online
2. There are super high level monsters in the base of the tree leading to the top.
3. Players can't fly to the top.
What are Kirito's thoughts about why it wasn't completed yet?
1. A undiscovered quest.
2. Requires the cooperation of races in order to beat the quest.
So this war of the races will be detrimental to Kirito's main objective, which is to climb the world tree, because he thinks that it's a cooperation of races to beat the quest.
What can Kirito gain if he helps the Sylph-Cait Sith alliance? He can gain their trust, friendship, and most importantly, help in order for him to climb the World Tree to finish his objective.
You see? Everything is intertwined and is ultimately important for the Rescue of Asuna.
It's not just a useless plot to drag the series nor it is like saving the Student Council instead of beating the MostEvilBoss.
As for battles not being consistent, there's an explanation that the Anime missed.