Fit n' finish questions from a new user

[Bedwyr]

Hello.

I'm about 80% complete on a CM3 mod, have "dry" fitted it, and wanted to ask some questions about final tweaks.

• The volume wheel is binding a bit, but I assume shaving down the bottom shell section a bit should take care of that, right?
  
• The D-pad is pretty mushy. Buttons are the aftermarket clear green ones. I see others have had trouble and say that adding some cardboard should stiffen things up a bit? Another suggestion was to add plastic? I'd like to not damage the rubber membrane if possible, but I'll do it if I absolutely must.
  
• The power switch button (cover? housing? plastic-bit-that-hooks-the-actual-switch?) is more problematical. I see that cutting the plastic bump leaves the switch button with a lot of play, letting it rotate underneath the PCB power switch (see pictures). I'm thinking of gluing a small sheet of plastic scrap to the bottom right of the switch button so it doesn't rotate under. I could also CA glue some scrap either on top of the twin prongs of the button or the bottom of the PCB switch itself.
  

<--- held in place it's fine.

<--- button is riding underneath the switch and doesn't "grab".

• The shoulder buttons are binding pretty bad when the top screws are tightened. Is there are read on where the binding is worse? I could shave off some plastic from the shell or the shoulder buttons or both if I knew where to do it so that it seats slightly looser.
  
• Last, I'm thinking of finishing the ports with Sugru to make it look a little cleaner, more professional. For people practiced with the epoxy rubber, would partially forming the Sugru on a port half and then seating the PCB in place to get the rubber squared up work or will the Sugru inevitably adhere to the USB, HDMI, and MicroUSBj ports?
  

<--- re: the USB port, "mistakes were made".

Thanks in advance for the help.