Your inspire me to want to sculpt and learn more. I use both my pen and mouse when I sculpt also. It seems easier to zoom and twiddle with the mouse than the pen. certain lines I have problems with, so I have to move the tablet around a bit. For me some times it the hand eye coordination looking at the screen and making a diagonal line on the pad on my desk. Kind of like playing with an Etch-a-sketch. I would like to try a pen display some time. I think it would be a whole lot easier. I did a little sculpting on my box, now I have to work on modeling what is going inside
Glad you are inspired! Your box looks great (thanks again to Michael M. for posting the perspective method!).
I use the Alt key for twiddling the model rotation and panning when using the pen. My tablet has keypads that function as Space, Ctrl, Alt, Shift keys and also has a zoom bar. Holding a switch on the pen body while holding down a tablet keypad (or computer keypad - same result) can speed up the process, as compared to changing over to your mouse. I will rotate the on-screen model (not the tablet) when I need a more comfortable angle whilst sculpting.
Another TIP: The Arrow keys on your computer keyboard are handy for changing the Tool Strength and the Cursor Size, when using the pen. You can press the horizontal arrows to reduce/enlarge cursor size...press the vertical arrows to increase/decrease tool strength.