Your tier systems (all of them) are innovative and probably worth at least a serious playtest/marketing write up. I sincerly hope that a few "sacred cows" come BACK into the game...
Classes not roles - it's a little thing, a naming convention, but this is probably the easiest point to something that makes 4e seems like an MMO to me. The idea of a "role" based solely on class makes my skin itch. I like to be able to play a class way outside the box, just because I can, it's very hard to do this when all of your "powers" are focused on a few set-paths. In trying to cast off the cookie cutter design, I think they painted themselves into a corner of epic cookie cutter proportions.
Magic for magic users - Powers need to leave. A mage should have a mystique when they use magic, it's different. When the fighter uses a power that is near magical, well, it doesn't seem right to me. I'm probably in the minority but the "wire-fu" explanations that are 'built-in' to the current system are a turn off to me. I think 3e went too far in making magic the be all and end all of the game (mages rule and everyone else can suck it attitude) but 4e's "everyone is a winner" attitude just reminds my why the US is near last in academic achievement.
Magic items need to be magical...and therefore rare. This is something that none of the editions have gotten completely right, but the original and Moldvay Basic/Expert weren't too far off on. The idea of fixed treasure tables (3e) and suggested magic by level (4e) is just wrong. (IMO) If D&D were a fantasy novel the bartender in the opening book wouldn't have to wait for the adventurers to save him, he would just reach under his counter and pull out his self-propelled howitzer of orc slaying and keep the peace. Okay, hyperbole aside, it is a problem, magic/treasure shouldn't equal level (or even XP - 1eAD&D I'm looking at you).
Simplicity - I remember the first time I played, I went to my cousin's house, he explained the game in about 4 minutes and we sat down and played. We didn't even have polyhedral dice, so we just went with what we had. Can you imagine trying to play 3e/4e with just a set of 6-siders? Is it even possible? The 'rules' should be there to guide not pigeon-hole. Yes I understand that with rules light comes DM adjudication and the ole' judgement call, but it's gotten so bad that you can barely play the game without a degree from a Community College in lower mathematics or statistics and probability (again hyperbole). How many kids can play D&D during recess? Is there such a push to make money that "accessories" and "product" are driving the game instead of fun?
No electronics - Okay, hear me out. I realize that computer hookups, video table tops, play by iPhone/iPad/iDon'tKnow is cool. But I want dice, not an interface, paper, not a screen and maps/minis not a top down display with 3D scrolling and real-life terrain simulations. I'm not advocating not supporting these things, I'm just saying, they should be just that, support - not the product, or otherwise, I can't afford to play anymore. If the game has gotten to the point that you have to have mounds of available cash/the latest equipment to play - then D&D has died. (And for the record, no my computer is 8 years old, I do not own an iAnything and my phone dials other phones...that's all, yes it's old fashioned, but I like it that way. Maybe I've been passed over by technology, if so, then 5e won't be for me - 4e is already too close to being too far gone.)
Customer support - okay this may seem like a weird request, but does anyone remember that when you contacted TSR, they would respond? And usually throw in free stuff to boot. Sure as the company got larger it went further and further away from the out of the basement customer service, but does it have to be release and dump? Oh you mean I need a subscription to an electronic service to get customer support? No thanks. Luckily I have ENworld to help, but shouldn't the company have something available that doesn't cost in order to get help with a problem?
No default setting - 3e blew it with this, 4e destroyed it. If you wanted a pre-made setting you used to buy a campaign guide. Otherwise the DM made a world and the rest of the players ran around in it. I don't want to know about the gods/goddesses, towns, countries, continents, racial alignments/affiliations and such that you think I should play in.... I want to design my own, that's why I DM. Before 3.X there was NEVER a default setting mentioned in the rules. Oh sure, they suggested things, but every world was handled by a separate publication dating all the way back to the old 4x8 white pocket booklets in the brown wooden box art set.
Greyhawk is awesome, Faerun is cool, the points of light was interesting but not for me, Athas, no, Planescape and the outer worlds - no thank you - Dragonlance - let's not go there... Give people a little credit for their creativity and profit off of it if they aren't - I would figure another book would be good for the profit margins....
Okay, I've gone on long enough - really, I want to regress a little in design, not a retro-clone or a ret-con of 1e - I want something new, but something that isn't ... so alien as to be unrecognizable. Soapbox gone, let the flames commence..