One important part you need to add: The equity vests over time. So if one of the co-founders leave they just walk away with the part they earned over time and not the same share as the rest that stays.
A vesting schedule is so crucial. Many founders find themselves in the position of being partners with someone who is all but inactive with a substantial portion of equity. Not only is it unfair to those doing the work but even if all parties are willing fixing the split later can be costly, time consuming, and have serious tax implications.
This is so important. It keeps everyone motivated and aligned. If someone leaves, they keep what they've earned, but don't accrue additional ownership.