Currently, there is no page that "suggests" battery and C rating for a setup. Part of that is because it was never designed that way, part is for liability, and part is because there is a project I'm working on with Mike, and I cannot say any more.
Furthermore, suggesting a mAh/C rate battery relies heavily on the fact that certain manufacturers are honest, which isn't always the case. Even though they may rate a pack for 5Ah @ 30C doesn't mean it will live up to it in the real world. So, someone may choose one of those packs and still have problems. Unfortunately, the only way to know for sure is to rely on other users' findings.
Finnster's method of using a power figure is perfectly fine, you just have to know around what a specific setup will require up front, and that takes experience which noobs don't have.