I had this problem too, so I don’t have any of my normal letter keys as dual-function.
The pointer-finger vertical-middle keys that they default to Hyper and Meh, I changed those to both be Cmd on MacOS (would make them Ctrl on Linux). I set the bottom row and pinky keys to also have lots of modifiers & layer toggles, and my pinky-fingers can hit those modifiers/toggles when needed. Then moved basically all symbols to another layer on easy-to-reach keys.
This means I can type regular words as fast as I want, and can easily reach any symbol when I need it. Only downside is that it takes some adjusting and practice, but I personally think it was worthwhile
The pointer-finger vertical-middle keys that they default to Hyper and Meh, I changed those to both be Cmd on MacOS (would make them Ctrl on Linux). I set the bottom row and pinky keys to also have lots of modifiers & layer toggles, and my pinky-fingers can hit those modifiers/toggles when needed. Then moved basically all symbols to another layer on easy-to-reach keys.
This means I can type regular words as fast as I want, and can easily reach any symbol when I need it. Only downside is that it takes some adjusting and practice, but I personally think it was worthwhile