That mix will give pretty good results. I have been making and using something very similar. The newest products with sumagrow inside have specifically selected micros that would not come from the home made brew(no way to know for sure how many or what micro organisms you would get). With all the University testing of these new "no fertilizer " products it looks promising, especially if the claims of 50 to 75% less fertilizer needed are backed up on a broader level.
So to make a substitute of the sumagrow product would be VERY difficult. To make a substitute of all the other "Lazy Man" and aerifing solutions is not a problem at all. You seem to be off to a good start