What difficulty do you play on? On Expert, in full glass armor with several light armor perks and 330 health, high-level enemy archers can kill me in two or three hits. Mages would rip me apart too if I wasn't a breton. It's impossible to stay hidden at all times, and when you're spotted, you'll wish you had more health. Meanwhile, my 250 stamina is enough to have Matrix-style fights against enemies if I wanted to do that. It's fun, but totally overkill.
Truth be told, I don't really think health is useless, I just disagree with anyone who says that stamina is. But my playstyle is never to be targeted, never get involved in a melee fight, because I know I'll get ripped apart - exactly for the reason you state. It doesn't really matter if I have 200, 300 or 400 health, I'll still get killed in an instant. It's better to focus on not getting hit.
I believe a decent stamina pool can be a great help to a sneak archer, that's all. Once you get to the point when you feel comfortable with its amount, nothing's stopping you from putting the rest of the points in health (you could start with building up health, though, the beginning can be pretty tough).
Btw, I'm playing on Master.
Well if you stand there like an idiot waiting for melee to reach you instead of sneaking away between every 1-2 shots so as to not get detected, then you're doing it wrong. And Steady Hand slows you as well, so it has no practical use other than being a crutch for people that can't aim very well.
I'm not standing there like an idiot, there are some areas when you can't hide back in shadows, not to mention that it takes some time before your sneak is high enough to make you practically indetectable.
I'm not saying everybody should put all their points into stamina, I'm just saying it's not worthless... Or, better, that it's not worthless IN MY PLAYSTYLE. You guys have different experience, I understand that.