Your suggestions sound eminently sensible to me, although I would settle for the first item and call it a day. More fundamentally, the article author seems to think that it is a problem that atime is slow on btrfs. Quite the contrary: it is excellent news, especially since it seems to be caused by the basic btrfs design principles (so it is hard to "fix").
In fact, once most people agree that there is no reason whatsoever not to mount everything with noatime, we can drop it altogether and start reaping the benefits. All operations are faster, the code becomes simpler, and we can put the now free space in inodes (both on disk and in memory) to more productive use. It is difficult to see any costs here—what would break? finger?
Then, once that has been taken care of, we can go on dealing with some other part of the baroque Unix legacy. Remove 99 % of the TTY options, perhaps? We can start slowly, by taking away the one that converts lower to upper case, and see if anyone notices.