Replacing tub/shower handle & cover plate

I have a Danfoss Tempress II (as in the picture).



I would like to update the cover plate & handle, and put in a new valve while I'm at it (the water flow is very low which I'm assuming is a valve issue). Is it possible to keep the same valve body/valve but update the cover plate and handle? I'm trying to keep this as simple as possible.

 

If you have access from the back, then anything is possible without changing things in the shower. If not, and you're willing to make a larger hole, they make remodel plates that fit underneath the trim you choose to cover the larger hole needed to gain access to install a new valve.

Some valves have screen filters on their inputs, and if yours does, that may be clogged, lowering the flow through the valve. There are certainly other reasons the flow might be low including a clogged showerhead, galvanized pipes, or other things.