I use keyboard to move on the ground, tracking pad in space. I am left handed and using a laptop. I have no number pad.
In space: I use backquote (left of the 1 key) as my fire key which keeps me near the number keys and saves the more important parts of my keyboard from abuse. One ergonomic defect occurs in space, when the game sometimes decides I'm not pressing both mouse buttons. If I don't notice until too late then I slam into stuff (if I hot-key Ramming Speed this is almost a 'benefit'). Another risk is hitting Esc by accident but with practice that very rarely happens. The track pad is close enough to the keyboard to also use my right hand for keyboard zoom-in/out and friend-targeting. The track pad is also always handy for clicking on things, but not when I need to steer. The greatest quality of life improvement to the game since I started is Control-Q/A/Z for pickups.