There are plenty of small spot light fixtures that you could use as accent lights on the layout. Look at track lighting in your local Home Depot/ Lowes. Most have adapters that will allow you to mount the fixture right on the box.
Soooo.....be aware that it is not permissible by code to leave unconnected (even capped or taped) wires buried in a wall.
25+ years as a licensed electrician and I've dug out my share of buried splice boxes. 
If you don't want to use them at all you can cover the boxes with a blank plate and put your scenic backdrops over them. The backdrops are not considered a permanent finish so no code violation.
