Well we (effectively) have 11 teams now and I expect the next Concorde Agreement is going to keep the maximum at 12 now that GM is in.
And yes, there is a theoretical "perfect" aero design for an F1 car, but even Max Verstappen, who is the most talented active driver in F1, cannot maximize the potential of it (starts at 7:40):
And yes, there is a theoretical "perfect" aero design for an F1 car, but even Max Verstappen, who is the most talented active driver in F1, cannot maximize the potential of it (starts at 7:40):