Just like the difference between proportional representation, and the variations of it, and first past the post, it involves trade-offs. Within all of those options you talk about that are available, there are trade-offs as well.
I guess I direct my concerns at proportional representation in a very general way, based on most of the suggestions that have been made. Of course, I would be open to a system that addressed those concerns, but I haven't seen it yet, because the more proportionality you want, the larger the ridings are probably going to have to get.