There are other ways to achieve this outcome. Granting of extra votes is probably the right mechanism. Classifying appointment / dismissal of CEO as matter Requiring unanimous approval may be ; but, per above comments, that is a big ask. You could also try having an exec employment contract w the company itself.
So, from the perspective of ‘best practices’, I’m aware of two relevant points. 1. As others have said, have the shares vested? 2. Are you departing as a “good leaver” or a “bad leaver” - these are terms that get used in founders agreements.
Without more detail, it’s hard to do more than guess, but sounds like it wouldn’t be totally unreasonable to expect to have your shares bought out.
What do the lawyers say lol