If you're riding in urban areas, I don't think clipless is worth it. There's too much stopping and you don't get the full benefits, but all the hassles.

That said, I think I improved my speed and climbing skills (well, not saying much) with clipless because you do get more power--you can utilize the upstroke. It's also really useful if you start flagging--I just tell myself to pull up, and it takes some of the burden of my tired quads.

Part of me would also like to take the pedals off so going for a ride doesn't have to be a big production, and I can just wear my regular shoes.

Don't change it because you feel you have to to be a "big girl." If you reach a point where you want to try it, for whatever reason (and yes, that can be "just because"), go for it.