Blizzard seems to be presenting D4 as a throwback to the earlier games in the series due to all the backlash from D3. The negativity I saw wasn't about the genre being stagnant or a lack of innovation but rather for departing too much from what existing fans expected. The auction house, itemization (skills scaling too much off weapon damage), the change in tone and art style, the story and cartoonish dialog are what I remember people complaining about along with the hacks on the console side. I understand where you're coming from but as a long time fan of the series a throwback Diablo game is exactly what I want. I suppose we'll have to see where everyone else falls but I think there is enough space in the genre for PoE, Diablo, and others to all do well. I suspect Diablo will capture more of the casual players with the bigger budget and refined D3 combat while PoE will certainly appeal to the segment that wants the extreme customization systems.
FWIW I did think the leaks about the canceled Josh Mosqueira game sounded great, I would want to play that game, just not if it meant no more traditional Diablo.
I get that and there's definitely some truth to that. When D3 came out, people expected a game on the quality level of D2 and the sad fact is that it just wasn't. Not even close. The Auction House made no sense at all for a game like D3, it was just shoehorned into the game half a year or so before release and it just completely ran counter to D3's core gameplay loop. But that wasn't the only issue, the D3 design team just fundamentally didn't understand some of the core aspects that made D2 tick. I usually never throw other designers under the bus, but Jay Wilson was just the wrong person to put in charge of D3. He was responsible for some core changes that just put the game into a state where it wasn't really 'fixable' even with expansions and so on (don't get me started on the Paragon system... a horribly grindy design patch on top of a fundamentally flawed system... terrible). There was no skill system anymore, they didn't like the fact that people were able to look up optimal build stats on a Wiki, so their response was to just completely remove the skill system, to remove player choice and weigh everything insanely towards itemization, which made the game incredibly shallow... and it also killed the fantasy. Playing a mage and running around with a heavy Barb two-hander completely broke the class fantasy, but that's what you had to do to gain an edge due to shallow systems.
I get that people would basically be happy if they'd 'just get another Diablo 2', but you're not getting that by just creating a carbon copy of a thing you already made. D2, when it came out, was pretty revolutionary. It improved upon every aspect of Diablo 1 and successfully so. It still had some silly systems in it (what in the world was the stamina / run shit for? I don't understand that to this day), but it was a damn fine game and the systems made the game almost infinitely replayable - D3 due to its shallow almost arcade-like quality just didn't have that. If you want to create the next big thing in a franchise, sometimes you have to innovate and take the next step, even if that step is a bit radical and might offend your old school fans for a bit (Until they 'get' that it's the right step forward). The proper sequel to 2d Mario at some point had to be Super Mario 64. If they would've gone 3d by doing what New Super Mario Bros did, nobody would have cared. Again, Point and Click Combat is a relic of the past. There's tons of games out there that show how the combat system in those games should work, but Blizzard at this point is just trying to do the same old, same old and that'll bite them in the butt, cause somebody is gonna come in and do it right.