Tactica - Howling banshee's in 2000 pt. list

[Levin]

I've recently put together a full 2000 pt. Eldar list using the new codex. But I'm kind of stuck now as I'm in uncharted territory with this kind of an army. I'm used to either hordes, or 3+ elite armies. Now I've got an elite army that is extremely fragile, and I'm afraid I'll have to seriously change up my play style to compensate for this. Anyway, my problem is this. Should I take a full 10 howling banshees?

I personally love the models, and in fact, they were what made me first desire to play eldar. The problem is, they're not that effective against all armies. I hear arguments all the time in favor of Scorpions, but I personally don't care for them and don't really want to use them. So, now I need to figure out if the Banshees are cost effective enough, and at what squad size are they Ideally.

A full squad of 10 (including exarch, executioner) with wave serpent is 182+115=297. This would give me 30 attacks on the charge (always going first) 3 at S5 27 at S3, all power weapons, hitting most enemies on 4's. This breaks down to approx. 15 hits. 1-2 of which wounding on 3's 13-14 on 5's... making 5.6-7 dead before they ever get to attack back.

That was against marines. termies would save 2-3 of those attacks. Does that seem cost effective to you? I've got another strategy that would include my farseer casting doom on the squad in question. This would greatly help out the wounds, and possibly allow me to blow through the entire squad. However, this would require me to find an extra 55-65 points to accomplish this.

Also, is there any way to accompany them with a warlock? I don't think there is but I don't have the codex here with me and wasn't sure. That'd be way better as it would allow them to be WS5/6. This seems more practicle than taking warshout that only makes the opponets WS1 if they fail a LD test.... not very likely on a 10.