Full Disclosure: I'm also a developer. :-)
You all have 25% currently. Even if the percentages are off, and you could change them I'm guessing you would be talking 5% +/- across the board. Any projects I've worked on line this we've done the same thing. Even split. The people coming in later are people that are needed to execute and we were basically in the same boat (a few weeks ahead of the new recruits).
I think you've done a fair split and I'd continue to follow the same approach for new projects. Look forward, focus on the execution, and hope it turns out that 5% makes a massive difference. Will make that 25% look even sweeter! :-)
Best of luck Xati!