You may as well argue for rack and pinion steering. It would also work just fine, if you can arrange it so your knees don't hit the wheel. I don't see how the steering would have made a difference to stability. I've controlled enough different vehicles in my life to adapt to different steering forces (including learning to drive on a Chevy Caprice with casually overpowered steering, and R/C planes and cars which have no force feedback at all) and that's not the same as stability.

The steering geometry is way more important. Like the location and height of the CG, caster, etc. I really felt the Terra Trike didn't have enough tendency to return to center. It was really neutral, I felt too neutral.

I'm also sure it would have felt a lot more stable with full suspension.