I don't even know how my reaction is to this question :I
Anyhow, I think Ashley's worst, I mean she practically does nothing. Except maybe that part in the game where you control her a bit. But overall, Sheva vs Ashley? Imo, I don't think they should even be compared :I
Damsel in distress vs BSAA member who can fight? :X
And personally, I don't think Sheva is THAT bad, especially when you're using a *good* real life partner with you. I also happen to use Sheva when playing with my partner xD;
I rarely play alone (lol), but when I see my friend does, all I could see is that she has pretty good accuracy XD
From the complaints I hear, I will, however, again, say, that she is much better when played by a real person :/
*hugs sheva tightly*