I noticed that most of the arguments in support of keeping
ethical alignments dealt with
moral quandaries. Since we know the latter are still in the game, I don't think you guys need to be worrying. Also, we don't know that ethical alignments are gone, but it does seem that way.
As for ability drains and level drains, not only were they annoying on a bookkeeping level, but the latter could cause major balance problems. The easiest way to drop a fighter in 3E was to drain his or her mental abilities, and the easiest way to drop a wizard was to drain his or her mental abilities. I saw this as being sort of counter intuitive. It does make a lot of sense, but I always saw the ability damage attacks and spells as ways to weaken your opponents' effectiveness, not drop them entirely; that's what HP damage was for. And for poisons, I think slowly ticking away a player's hit points will scare him or her just as much as damaging one of his or her ability scores.
I think rogues being able to sneak attack [everything?] leaves a lot less logical inconsistency than the current system where they are unable to sneak attack large swaths of monsters, many of which with obvious weak points. Also, remember that HP are definitely an abstract in 4E; there is no discussion over it as there was in previous editions. Because of this, it becomes much more easy to see how a rogue can sneak attack a whole larger variety of targets.
As for the races and class changes, I can see why people get upset about it because of flavor. It is a change in "core" D&D flavor. On the other hand, the logic that it wouldn't be "realistic" to have these races able to move freely about the world is a little weak. For one thing, the obvious assumption is that these are known and fairly common races, so they're not going to strike the average fantasy townsfolk as a horrible monster. Also, if we're going to take real world country bumpkins as the measuring stick for our fantasy country bumpkins, shouldn't they hate anything not of the same race as them. I mean if skin color can cause such ire, shouldn't differently shaped ears, very different proportions, and a tendency to have either a whole hell of a lot of facial hair or absolutely none at all logically end up with someone saying, "Jethro, get a rope"?
And while the core assumptions include a distinct change in flavor, I don't believe you have to change your own flavor to match if you want to still include Dragonborn or Tieflings or whatever. What I mean is that you can keep these races as rare, mysterious and potentially hated by common folk of the world. Drizzt and Viconia from the BG games are good illustrations of how this can be done. (I know, I'm sorry I'm using frikking Drow as examples of how to include "evil" races. I'm even less creative than the 4E designers.

) Drizzt earns his way in the world with his actions. Because he has proven, time and time again, that he is definitely not evil, he is now welcomed throughout the North and in a number of other locales. Viconia, on the other hand is through and through evil (and a total b*tch; talk about "kiss me; diss me"), but she finds herself able to travel relatively freely on the surface when she's in the party because she's either adventuring with a group of heroes or a group of people to frikking BA for Joe Dalesman to mess with. Both of these characters come from an uncommon or downright rare race on the surface, but they're uncommon people; they're adventurers!
For the most part, I agree with everything else in the OP.