I have built many floor layouts over the years. I have found that there are ways to hide the wires in plain sight. The key is not to run the wires helter skelter all over the place, but route them together in bundles (dress the wires). I try to square off the corners and route along tracks. If a group of wires must go under a track, I do it all at the same place. I make wire routes on the floor, and as a last step wrap the bundles with wire ties or extra wires. Not perfect, but it helps. Here is a picture of what I mean