Try holding a wheel by the spindle, one hand on each end, and get someone to spin it. Now 'steer' it; due to gyroscopic precession the reaction is felt at 90deg to the input force.
Now try the same holding just one end of the spindle; the forces are immense trying to twist (and succeeding) the thing out of your hand.
The good news is you don't have to clamp the spindle at just one end, unless your business plan dictates that marketing gimmickry is the most important aspect of your design. Cannondale, I'm talking to you.
I think your over simplifying things and these are not engineering issues which can not be resolved and have been, high performance motorcycles have featured single sided swing arms for years and is not considered to be an issue. Likewise motorcycles with single sided front ends have also been produced such as the BMW d1200r
http://thekneeslider.com/d1200r-bmw-goes-into-limited-production/
Unconventional but by no means bad engineering imho