I use the numpad, arrow keys, and home cluster all the time, partly because entering numbers and moving around spreadsheets is a significant portion of my work.
Dedicated keys are important to me, I hate having to toggle back and forth. I particularly like using the Enter key on the numpad and use it more than the regular one.
When I went shopping for a laptop, a numpad was a big plus for me.
A year or two ago, I saw a post somewhere about left-handed mousing. Although I am strongly right-handed, I LOVE the mouse on the left. Besides fixing the "far away right hand" problem, my dominant hand is also free to write, answer the phone, etc.
It was painful for a week, and awkward for a month, then I never looked back. Highly recommended.
PS - I am an old goat, you youngsters could switch much faster.