I think that you should base the addition of hypo on silver rather than gelatin, and you should also consider the size of the grain. More hypo is needed as the grain size gets smaller.

The first ripening is usually right after the emulsion is made and contains no hypo, and the second ripening which is called 'finishing' or 'chemical sensitization' is carried out in the presence of hypo.

There are few real modern finish formulas published anywhere, but I will tell you that they are as complex as most modern emulsion formuas. The simple ones that use hypo and heat are really old and rather primitive, but they do work.

Some emulsions do not require any finish depending on the speed you require. I have seen excellent camera speed (ISO 6) emulsions with no finish, so it really depends on what you want.