In short, the CEO is in charge of all formal undertakings of the company, unless and until he delegates some of his role. The CEO ensures that the shareholders' agreement and the votes during the General Meeting are adhered to. Further, he remains the main point of contact for administrative bodies dealing with the SAS.
In any event, the statutes cannot violate the rule according to which the CEO's powers are limited by the social object of the company: as such, a CEO who acts outside the scope of the company's activities will be liable for any damage or loss resulting therefrom.
Regarding the choice of the CEO, one must be mindful that this is not the most important consideration at the start of the company's life. We would advise that you choose the individual who will dedicate the most amount of time to the company and who wishes to be a public representative.
To ensure balanced relations between the shareholders of your SAS, you may confer the its incorporation and drafting of statutes and shareholders' agreement to Alf. For more information, don't hesitate to contact us or consult our Company incorporation page.