How are you testing for all the minerals found in salt mixes? Looking at your spreadsheet I see you are testing for the usual stuff plus Iodine, Iron, Boron, Strontium, and Potassium. Also what did you base your target levels on? Was this based on what you found in a fresh batch of water or natural seawater? What about silicon and bromine and other trace elements? How are you going about replenishing these or testing the levels?
This sounds similar to what the planted tank folks call EI dosing to ensure their plants get what they need along with the right amount of light and CO2, but they also do things a little differently and perform a weekly water change to "reset" their numbers for the following week's dosing.
Water changes aren't necessarily cheap and I can also see how water changes alter water parameters which can cause swings in the parameters. With reefs stability is a big thing. The dutch had an influence on this side of the hobby as well.
One other thing are you checking your ORP? What are you doing to maintain an acceptable ORP? I'm not arguing that water changes are the only way to maintain a healthy reef, but I do sometimes think too many can have the same effect as neglecting your tank. Things like your water being "too clean" or huge swings in parameters because of the differences in Alk, Ca, Mg, pH etc can also have an effect on the inhabitants.
How long have you been maintaining your tank this way? With this method what do you do when something gets off or too high like if your nitrates or phosphates get too high? Are you just skimming more aggressively and increasing chemical/mechanical filtration? What do you do if altering the filtration doesn't start to bring things back into an acceptable level? I'm no expert on water chemistry, but I'm very curious about your method.