A general rule I stick to is that the person who gets a salary gets less than 2 digits equity early stage. Same applies for founders who work 40 hours a week and so on.

How important is everyone to the success of the startup? If you have 5%, you should be increasing the valuation of the company by 6%. 26% share should increase valuation by 36%. 36% share increases it by 57%.

However, this assumes it's unpaid. The ones getting salary need to increase valuation by far more.

I don't know the credentials, but if the two larger portion guys play a big role in valuation, it should be fine. E.g. good degrees, previous experience with startups, investments, rare skills.