Your renders are not bad at all. I think it’s just that maybe they can pop a little more 
For sure, in order to make a Keyshot render pop, Photoshop is almost definitely necessary.
I pretty much always use a High Pass layer to give the image more defined sharpness and sometimes add reflections, glares and noise on separate layers.
Another thing to keep in mind is the lighting within Keyshot and playing with depth of field.
To me, lighting is almost more essential than the material selection and I pretty much never use the standard setups.
For example, the Startup HDRI is way too dull, imo.
This is a personal observation but I have always found it easier to render dark materials than lights ones.
I had a few minutes during lunch so I took the liberty of seeing what I could do with the render you provided.
It’s always kinda silly suggesting stuff and then not showing it
Thsi can definitally be waaaaaay improved and to get really good results, you would probably have to re-render it with different lighting and then edit a high-res version.
Also what the render should look and feel like is highly subjective but personally, maybe this is where I would try to take it… kinda.
