Each player can have 8 characters, would 8 view entities be too many?
The answer is a clear "maybe". Seriously that totally depends on the number of polys, used shaders, target running machine configuration etc. A good rule of thumb is to test it on a pc that has got the lowest machine specs you're expecting your customers to have. If it runs, ok, everything is fine. If it is too slow, you better have an idea.

If you're doing the game just for yourself and some of your friends, well then nevermind.