Mark, I would strongly recommend against this formula as a practical formula. Despite your observation, formula like this is very intolerant of small errors and performance will be very much variable in practical situations. You are getting into roads that careful chemists avoid.
Borates are very useful buffering agents. There are some known downsides, and I wouldn't use it unless there is a good reason to do so. But any chemical ingredient that has any useful property has good and bad aspects. If you remove the buffering capacity and alkaline agent (borates) from your formula, you must balance with something else. You have to weigh risks and benefits of using each and all ingredients that go into formula and make a rational judgment.