I used a bow on my archer but think that xbows>bows.
From what I remember, I hardly ever use regular shots anyways... with full-cooldown on aimed shot, power shot, and mist, there's always a skill that's cooled down and ready to go. Even with single-targets, I use mist anyways because I have it maxed out on power and it does quite a bit of damage.
The only pro I see in bows is that it gives you an extra shot if you press attack after you use your skill.
As for SP consumption, I use a lot of SP. xD But I like to be able to do lots of damage as well so I pass up SP for more damage hahah.
NS doesn't help me much, because even when I have NS on I'm using skills anyways... which makes me feel like I'm wasting the buff. xD