Personally, I have found that keeping things from between the speakers helps imaging in most setups, especially if they protrude in front of the plane like you said. (It also looks cooler.)
But, in my setup I've decided that optimizing for distances from speakers to walls, distance between speakers, and distance to the listener have a much larger effect. Again, this is personal preference, but I find that filling a larger volume of the sound-field is better that keeping reflective surfaces really far away. In fact, I even have a 7" square support post for my house in the sound stage! It's a big problem, for sure, but solving it makes even bigger problems. IMO if it solves more problems than it creates then go for it.