i'm going to design and build a "programmer's numpad", because I'm sick of awkward hand movements for writing brackets with numbers and commas and spaces etc. here's the first draft. make your modifications here: http://www.keyboard-layout-editor.com/#/ i'm thinking of adding another column, putting something between the numbers and the plus/minus.
Pinkie on the shift, hit the square bracket with your thumb
Right shift is nearby if you prefer hand stretches over using both hands