Save the pedantry for execution, not micro-managing equity splits. To me, job No. 1 is keeping your small team happy, united and focused. I don't think you maintain the camaraderie necessary when you're tossing 5% and 20% bones to people who did this vs. those who did that. IMO, people who come in at roughly the same time should get the same stake, assuming they're equally focused on the task.