You can become much faster using MathType if you just give in and learn a couple of little shortcuts… then no more reaching for your mouse all the time.
TAB or Arrow Keys will move your cursor around the fields
Ctrl-F for a fraction
Ctrl-R for a radical
Ctrl-H for a high script (superscript)
Ctrl-L for a low script (subscript)
Ctrl-J for both high and low scripts
Ctrl-Space for a Space