I'm actually concerned about the graphic design of my startup. There is a pay-for-service component to it, and I have this feeling that if it doesn't look professional, no one will trust it. Anyone think that is a valid concern?
If it's something remarkable then it won't matter as much. People will just want it and might look past things like design to get it.
Usually though when people are opening up their wallets they want to make sure the service is credible and the overall design is the first thing that helps them make this distinction, followed by a blog, founding team descriptions, press mentions etc...
It also depends on your audience. Are they more web savvy?
Maybe the best approach to take when good graphic design is in short supply, is to keep it simple - and strip back all graphic elements that have no strict purpose?