Wow, I can tell that this brings back some painful memories. Honestly, a few of the ways would be make numerous button combos work. Create a forward button widget with a shift key widget on the top left and/or a Ctrl widget(sneak) key on the top right. Allowing people to choose in the moment exactly how they would like to proceed.
Or how about taking two buttons you use constantly and have them connected somewhere. This would turn the only two buttons into a combo. I’m sure other people have their own ideas, but the more features/options you give users, the better.
In fact, why not create a beta/experimental build for people to test these things out?