If you we're going to run 4 hunters. Then make sure you only activate find the path on one of them. As soon as you start putting on 3 or more of the same aura within the group, it bugs out. This affects any fellowship wide aura skills such as minstrel tales, hunter find the path, captains in defence of middle earth and runekeepers rousing words.

Ive never really tried to have a mixed group, I find there is to much of having to move the toons around in end game instances. But I have heard of some people doing it successfully.

What server are you on? I'm on gladden, which is a medium to high population server for US. I'm actually on the Gold Coast Australia but there is also a good hand full of Aussies.