I can see how being a friend might complicate moving further. I had a friend who liked me for a decent amount of time in high school and when he came out and told me, it totally took me by surprise and I didn't know how to handle it. We sort of drifted after that because it became awkward :<
I'm actually pretty oblivious to how people feel about me (as I, like many, am my own worst critic) so when someone comes right out and tells me I'm often not quite sure how to react (that is, unless if we never took the time to really know each other. I know how to handle those lol). If you're friends with someone that you want to start dating, my opinion is that you need to drop hints first, otherwise you'll stay in the friend category :/
Also, it's better to let the person at least consider the possibility of you two becoming more than friends before you come right out and say that you want to be with them. So, be courteous and drop hints (and, you know, GOOD hints... not creepy ones lol).