You think you're making a point by repeating the obvious, but you're not.
The studio's intent is to maximize the public's interest and the likelihood that a film will succeed, based on their best understanding and experience (however limited and shaky that may be in a lot of cases) using the resources they have. Piddling around and saying "oh, this works sometimes, this works sometimes...this worked once..." is meaningless in that context.
They can either try to attract attention by virtue of the actors they announce or by the characters who they are being cast to play - and the very best thing is to be able to do both.
There are no other individual antagonists in the Trek continuity that are of any publicity value whatever. The closest runner-up to Khan would be the Borg, as a group, so those are your choices.
The studio's intent is to maximize the public's interest and the likelihood that a film will succeed, based on their best understanding and experience (however limited and shaky that may be in a lot of cases) using the resources they have. Piddling around and saying "oh, this works sometimes, this works sometimes...this worked once..." is meaningless in that context.
They can either try to attract attention by virtue of the actors they announce or by the characters who they are being cast to play - and the very best thing is to be able to do both.
There are no other individual antagonists in the Trek continuity that are of any publicity value whatever. The closest runner-up to Khan would be the Borg, as a group, so those are your choices.