As for elitism of battle > siege...
I play a lot of both and generally do well enough in both - a little better in siege cause im used to it and because as infantry, sometimes battle can create scenarios that are difficult to deal with.
There are some SUPER good players in battle like San, Riran, Rohy, Cyranule, etc (NA people) and they come to siege and rape - but THEY RAPE in battle too just the same way, so that doesn't prove anything about the skill levels of the general population. Players from battle that are not as good as those types of players come to siege and from my observation do not do any better than they do in battle.
Honestly? General population - I find siege's population on NA to be just as good as battle's overall. Siege on NA has become a small and vet filled conflict and so sometimes there's more "easy kills" in battle than in siege on NA.
Plus, many of you may find this counter to your thoughts - but having played a lot of both I generally find my performance in battle to be MORE situational (a result of teams or team makeups) than in siege. You will lose a siege round if the other team is stacked, but your personal performance may not be as effected by it....whereas in battle, you will lose AND you have no hop of doing anything when your team gets steamrolled (unless you are one of those really good players I listed above or similar).
So again, the best players are good in both, and under that (at least in NA) I find siege to actually have an equal to or slightly higher general skill level.