No, I don't think it's wrong or weak at all to be agnostic. I think it's an intermediate stage between primitive religious belief (gleaned from organized religions) and more advanced spiritual awareness (going way beyond organized religions).

Agnosticism is a step on the road to enlightenment. For many people it is a necessary and a very valuable step on that road.

It implies open-mindedness, as opposed to the kind of fanatical, rigid certainty adhered to by members of fundamentalist religious faiths.