I noticed that every layer has properties rendered in the debug console.
Does these properties requires alot to calculate and would having lots of them slow down my game?
I use a lot of layers and it hasn't been a problem. Remember that debug is always slower than actually running the game--not all of that stuff you see in there is displayed constantly at runtime. I don't think I've gone past 30 layers, but the layers are just containers of objects. Nothing more. They're functionally identical to putting all of the objects on the same layer and possibly multiplying movement and positions to account for parallax values. Effects and Force Own Texture layers are the only instance where that's different because then that layer is rendered by itself and then placed with the other layers.
So just try it out, run tests, and change things if it doesn't work.