Oh man, same boat. (Though for me I'm just making a whole blog instead; I found it more flexible to my needs.)

The best general advice I can give, is to define early and clearly what features you want, and to stick to that. If you get any idea for extra features along the way, reserve them for a future version. This will help you break down the work, and avoid scope creep.

Have you already chosen a framework for the front and back ends?