If a snake is eating, shedding, and expelling well the snake is usually in good shape.
Not using the warm hide as much as it once did is no big deal. I have some snakes that hardly ever go to their warm spot, even after eating. As long as the ambient temps are good the snake will be just fine.
My BP is one that 99% of the time is in her cool hide and she is completely healthy.
More cover could be good but if it was my tank I would cover the back and maybe the sides to block the view of the wires. I use thick art paper on my two tanks. I secured it with electrical tape which blends into the top band on the tank great. Turned out to give it a really clean look. I also found it insulated the tank a bit and raised my ambient temps a couple degrees.