Comparing creatures that have wings, breathe fire, and are 40 feet long to a puny human is not reasonable. And that's before you consider magic.
By this reasoning, the game system itself is unreasonable, because that is exactly what it's meant to do.
I quite agree with the spirit of the tightening of rules, but some (GM may simply decide that cheesy strats don't work) should be... Well; self-explanatory, since the game tells us that whatever the GM decides is right, basically.
Other things are possibly solutions that only work against people who treat the system as a book of law, and try to find any loophole. To people like me, they don't mean much, and seem to overcomplicate things.
I do complete agree with your take on miss-chance, and have used a similar idea myself for a long time. I also love your tier-system of conditions! It makes no sense that someone could take both the penalties of being blinded as well as those of having blurry vision. Thanks for making a clear and understandable list!