there is no definition of a teatray in the rules.there is a definition of a flat bottom -if you decide to put your suspension in that area there is nothing to stop you doing that as long as you can place the plank where it is defined to be .
I cannot see where a current formula 1 car has any advanatge in terms of swing arm or camber control - teams seem to deliberately introduce horrible scrub and things in bump and with paralell equal length wishbones your cambers in roll are all over the place -my reasoning here is -suspension geometry and change ander dynamic loads is a low priority.
As with the steering still up there I do not think this is a given .Obviously such a radical design is far more than we will ever see in F1 ,maybe rightly so but i would still love to see a team taking a bold step ..
Fittingly Mr.wirth and his designs were epic fails at least in formula 1 ....I did not miss that little detail...