I think the person who should be CEO should (ideally) be the a) the person who brings the most to the table (in terms of that business) and b) the person who can inspire the team (and embody the vision). Often, these are the same people and then the decision is easy. Sometimes, you'll have a very technical company (Tech needed) with a consumer facing product (Inspiration needed). Then it gets harder. But I would never sit down with anyone and say "you bring more to the table but i deserve more." The bringing more to the table indicates the kind of position you should be in the company.
I'm also not saying that the non-CEO person is going to get zero - far from it. But if someone is going to get miffed over something that small that early, I think that's a pretty serious red flag for us not being able to work together.
Part of the difficulty here is that I think we have very different pictures of what we expect a CEO to be. Early on, it's not like you're going to have 15 different c level execs. If you have a tech business, guess what, you have a tech CEO (and probably no CTO). If you have a marketing business, you probably need a marketing CEO.
I've been both several times - and I definitely understand both positions now. If I joined a company, and wasn't CEO, i would absolutely understand why they were getting more than me (and I would hope they would understand the reverse).