Suspension - Soft or Hard?

True, mostly. It depends on the rear arm geometry which changes significantly once the car has been lowered.

On the subject of actual arm geometry, and something I found out recently which is quite interesting:

McPherson Struts on the front of most cars (S bodies particularly in this instance) gain negative camber under compression until the lower arm angle is less than 90 degrees relative to the axis of the strut. Then the opposite happens!

I had a peek under my SX properly the first time I went to get it aligned back in January when it was just on springs and was surprised at how much the lower arm angle had changed with perhaps a 40mm drop compared to where it should have been. Much more than this and the front geometry will be reversed from it's intended purpose

 

You're missing an important part of the bigger picture and that's the conical distortion of the tyre that results from camber.
With negative camber the inner sidewall is distorted and smaller than the outer. This helps the tyre to resist lateral forces and incrases grip. All OEM Sport geometry includes more camber, not less. This can give a more severe break-away once the tyre saturates though, which is why some drifters do without.
It also suits radial tyres which load-up and grip gradually harder and harder, rather than cross-plys which immediatly grip, then gradually let-go.
Only excessive camber would distort and spoil the contact patch.

All cars react differently to diffeent set-ups as do different drivers. We could drive the same car and have different opinions about how it drives, which is why it doesn't make a whole lot of sense for people to pass around geometry positions, though I appreciate why people do.

Hmm, not sure about that. Problem is it's almost impossibile to measure dynamic camber gains so you're in the realm of computer modelling and high end suspension design. TBH those gains likely to be minimal with a slammed & stiff set-up anyway