Okay, lots of stuff here, one thing at a time. I agree with the first half, and it's coming.
Somebody just has to do it.
I haven't had the time recently, and I haven't seen any patches yet. I disagree completely with the second part. Let Apache decide which of these should be used and when. If sendfile doesn't exist, then we won't define that feature macro. I suggest ignoring this for now, and maybe coming back to it in the near future.