After some time meddling with the control settings, I realized a way to fix the issue with Mobile users' lack of vertical strafe:

An option for Tilt Control paired with touch based roll

This way, one can turn their device to orient their spacecraft, and use touch based control to roll the spacecraft, the available vertical axis in the touchpad can be used to allow the user to strafe vertically.

Implement Droidbuttons. That is all.

DroidButtons is great, yes, but its more designed towards power users, and will likely be too complex for many. Also, it does have its limitations and issues.

The OP didn't ask for DroidButtons, he made specific suggestions. Let's keep this thread to those suggestions. Discussion of a fully configurable interface is really a topic for a different thread.