Sinon's first sniping shot in the only fight we have seen (the monster fiasco doesn't count) was like one of my better shots in Arma. Seemed pretty realistic in many ways, provided she's a levelled up sniper (since it's also an RPG that ought to allow such skill ups).
But you are right in the sense that I'm basing a lot on nothing but my opinions and first impressions. And so are you because this show is starting slower than Nanoha Strikers with absolutely nothing worthwhile to judge so far. We simply haven't seen enough yet, especially not a single fight from Kirito.
I don't know why I need to repeat this but according to Sinon, who's apparently an elite player, nobody uses the light sabers and they play little role in the game. Since I'm a Star Wars fan, you won't ever catch me calling them garbage weapons, but according to Sinon most GGO players must view them as expensive toys. I'm not sure what sort of Star Wars games you have been playing if you are under an impression they are useless in SW games, but Governor Tarkin would have commended you.
To put it in simpler words: It's not an SW game if every other player isn't carrying a light saber. Or in reverse: If every other player isn't carrying a light saber, they aren't worth it in the game. Yet suddenly they will be worth it if Kirito decides to use one.