Capital partner and Developer splits

edited/updated with answer to investor role
I’ve worked in development for 5 years now and sourced one on my own for equity, which I’ve written about elsewhere on WSO. But like everyone in development, I want to break out on my own. I have found a capital group who wants to partner with me to do developments - they source the sponsor equity and I do the work, then we partner with an institutional GP to do the heavy lifting, so we do not get a promote because the institutional partner takes the risk. Because there are more players in this structure and no promote for us, what is a fair split of the limited project resources? I know that whatever money people put in, that is their equity, but what about over and above that? I've decided that investors who contribute the capital, even though it is ast the GP level, are still serving the function of LPs and should expect only the project returns, nothing more. So that leaves...
1) Me (developer, sourced the deal, doing predev and will serve as local developer to the big guy) - I assume I should get most of the Dev fee, but this will be split with the institutional developer as well
2) my capital partners who source the capital to be the sponsor and control the land

EVERYONE (besides me) is asking what is their upside and how much more can they get over and above the equity. But there isn’t that much to go around without digging too much into my Dev fee.

What is fair? Please, if anyone has suggestions that would be awesome - even if you don't know real estate, what seems a fair split? 50/50, even though I'm the one doing all the actual work?