If I build a bridge, and the other side has bushes it will never get built because its waiting for the stuff on the other side to be cleared.

With no way to cross a river before the bridge is built you can only build one to where it stays clear on the other side.

Yep that's an issue, I'm undecided whether to leave it as-is to make it more difficult to find spots to build bridges, or auto-remove bushes on placement to make it very easy.