Just based on what you've written here, it sounds like this person is not slowing down the team, but rather isn't "pulling his weight" on the development front. Consider that:
1) He has successfully brought on quality dev talent (you) and could likely do this more as the company grows. He's willing to hire people better than himself, which is more rare than you might think.
2) Angel & seed investors, who typically invest heavily based on the team, have already signaled their opinion by investing.
3) He is likely taking on a meaningful amount of non-development busywork that comes with any small business and that is incredibly thankless.
If anything, I suspect your raising these concerns to the CEO is telling them more about your own level of workplace maturity than it is about the other person's development skills. Startups are hard enough without coworkers sniping and complaining about who's doing the most. If you're worried about who gets credit, it's going to be very difficult to go from promising concept to a sustainable high growth company.