1) First philosophy: blizzard want a character with blue rare and legendary at the same time. It worked at the beginning, a wizzard of method killed diablo inferno with a blue weapon mixed with rares. But then people complained "why a blue is better than a rare and legendary, etc" and make blizzard think again.
2) Second philosophy: "We agree legendaries are bad", buffed and happened what I'm afraid of: rares are nearly useless, and everybody looking the same gear, it feels like: if you don't drop this you're garbage. Legendaries have some fixed 50%+ god affixes, and comes to my question: is this good or bad? don't this devaluate rares too much? how many runs I see players leaving rares on the ground and just getting legendaries now?
3) Third philosophy: "MP and Paragon will give the game more end game". I agree with that, but we don't have ladder and the game don't even have a year. My point is: don't this devalue MF and GF too much as a long term? I mean it's another affix that sooner or later will be useless, and it was meant as an affix that worth your choice at cost of dps.
In short: Blizzard is confused about it's own philosophy, there are so many OP affixes that even if they buff life on kill or thorns it's still going to be useless, because characters reached a level of nearly perfection I'd say. Probably the only fix is some kind of nerf/adjustment on the trifecta, resist all etc.
Oh before I forget, they have to improve what they have now, the system right now, fixing some numbers, etc. Putting D2 idea into D3 it's nearly impossible. Is the same thing as saying: Guys we failed, we should've started that way from the start.
Everyone complained about Leggi items being horrible (which it was) now everyone just leaves rare on the floor(farming Leggies) when they do runs because 99% of all rare items is absolute garbage, i mean a wichdoctor ceremonial knife that drops with 300 dex ? But then agian there is that 1 in 10000000000 chance that a rare can be godly and be a 1bil or 2bil item. and not to mention everyone has vile ward shoulders..there is no real custimization for each player. but the game will only get better not worse Blizzard is doing a good job trying to get to everyone's needs. 1 step at a time. i can assure you when pvp gets released it will be unbalanced as hell and with time it will get balanced but that is (when) pvp arrives