I think that all three of (talent, skill, confidence) are useful. You can get pretty far on just one, but the more you have the easier it will be to get better outcomes.

And I can think of two different kinds of confidence -- self-confidence (I'm good enough at this to succeed) and perseverance (I suck now, but I can keep doing this until I succeed.)

I'm not sure what the second question means. I read it as, "do you think confidence is more important than talent to grow as a person?" or maybe, "do you think it's more important to develop confidence than talent?" Luckily, my answers to both are the same :)

"more important" doesn't quite express what i mean -- being confident and adequate (not skilled, but not totally incompetant) will get you somewhere, whereas being skilled but having so little confidence that you never do anything with the skill won't get you anywhere.

and i'm not sure what you mean by the second one.

For the first, the two are related: you need confidence in order to try; you need skill in order to succeed. So you need both.

I'm also somewhat confused by the 2nd question. If you mean "Grow as a person", then I'm not sure where talent enters the equation. If you mean "grow in a particular area", like, say, as a pianist, then ... I'd say again, you need both. It's a matter of what limits you. At first, you're learning, so this is just the first question re-phrased. But either you hit the limit of your confidence or the limit of your talent and you stop getting better.

Well, or the limit of your interest, or patience, or any number of things.