Blizzard did a lot right with Diablo 3, in terms of duplicating Diablo 2's gameplay and removing many of the annoying elements. But there are also sooo many completely boneheaded design decisions that it really makes you wonder how people get paid to make one terrible choice after another, and how nobody else objected at any point during design and development.
The skill system is a complete change from D2, and though it's different, it's fine. The main annoyance with the skill system in D2 was that you were heavily penalized for experimenting, which is obviously terrible. Simply giving players unlimited respecs would have completely solved that problem. D3's limited skill selection is certainly more restrictive than D2, and lowers the skill cap considerably, but I don't object to the designers drifting away from the standard skill tree, which can be argued has structural issues unrelated to whether or not you can respec.
Itemization is completely imbalanced in D3. D3 was always going to be a game about killing lots of stuff over and over again and hoping to get good drops. If you object to that particular type of gameplay (and I'm fine if you do), you're just playing the wrong game. If you don't like farming items, don't play Diablo. But the frequency and level range at which items drop in D3 is absolutely terrible.
The vast majority of stuff that you drop in D3 is going to be 8-12 levels below you, and it can't possibly be relevant to you other than putting it up on the auction house for cheap. This has the effect of flooding the auction house with cheap and easy items, essentially allowing anyone to "twink" themselves for very little cost or effort, simply by visiting the auction house.
I'm not opposed to the idea of the auction house per se, but when the 100% best way to progress through the game -- from 1-60, through all difficulty levels -- is to use your abundant excess gold to buy cheap stuff other players flood the AH with, then the designers have failed. Of course, part of the reason the AH is "too good" is because blues (magic items, in D2 lingo) are WAY too good, and legendaries (uniques) SUCK.
It's as if the best legendary items you can get in D3 are equivalent to exceptional uniques from D2, while blues can (and do) drop at elite. The disparity is THAT big. But blues are very common drops, while legendaries are exceedingly rare. So the exceedingly rare items just SUCK. They are TERRIBLE. But the really common items are AWESOME. They are easy to get and anyone can get them. The auction house is full of them. Everything is ass backwards, and dropping legendaries has none of the excitement that dropping uniques had in D2. In fact, you would prefer to never ever drop a legendary item.
Something else that is completely and utterly backwards is relative monster difficulty in Inferno. Inferno mobs are much, much, MUCH harder than the ACTUAL GAME BOSSES. For example, after you beat Diablo in Hell, if you could somehow magically teleport to Diablo in Inferno, you would be able to beat him. This is not hyperbole, and it's true for every single boss in the game, except The Butcher, who is the only boss with an enrage timer (so his fight is a DPS check, which you need a certain fairly low level of gear to pass.)
The Inferno bosses have no new mechanics, and their existing mechanics are all very robotic, easy to learn, and require nothing resembling strategy or teamwork to master. The only way they differ from their Hell counterparts is they have more HP and more damage. That's the way D2 did it, and I guess it would be OK if D3 did it the exact same way (but you hope the designers would have found a way to improve upon it ...), but D3 actually does it far worse. In D2 bosses were at least a gear check. In D3 they are a nothing check. Are you in Hell? Congratulations, you can beat all the Inferno bosses. You can't GET to them, but, hey, you could walk all over them if you could.
A1 Inferno actually is fine. The mob difficulty is ramped way up, elites spawn with some crazy combos of affixes, and it's legitimately difficult to work your way through it the first time. Then you get to The Butcher fight, and he enrages after 3 minutes and spanks you. You eventually realize you need to just spec max DPS, maybe gear up a bit, and he goes down smooth. Compare that to Act 2.
When you set foot in Act 2 for the first time, you are going to get SMASHED. The mobs are impossibly difficult. You need much better gear to be able to get past them. That's reasonable, I have no problem with a difficult game, nor am I morally opposed to the idea of gear checks as a means of impeding progress (though it's admittedly lazy design if that's all your game's got.) But then you get to Magda, and ... you trash her. If you can get to Magda legitimately, you will almost certainly utterly destroy her the first time you try. It will not be a challenge. Magda (and every Inferno boss except The Butcher) is simply easier (and MUCH easier) than the mobs you have to wade through to get to her. The bosses are an absolute joke.
Never mind that Blizzard really, REALLY made it sound like Inferno was going to be difficult and awesome and hardcore, and we were all in store for some amazing new gameplay mechanics, and the game doesn't really start till Inferno, etc., etc. They talked it up BIGTIME in interviews and previews and the like. (They said things like "people are going to wipe for weeks and weeks on the first boss" and "it will be months before Inferno is beaten.") Never mind that. It's terrible simply from an aesthetic perspective that the actual bosses of the game, purportedly the strongest demons in the world, would all get literally destroyed by trash mobs.
Some people (including blue posters) have been trying to defend this terrible design by saying stuff like, "Well we've/they've been saying the whole time we/they didn't want D3 to be like D2 where you just run bosses over and over again for gear. Of course the Inferno bosses are going to be easy, they drop trash." That reasoning is soooooooo dumb.
First of all, I really fail to see how endlessly farming elites is any different from endlessly farming bosses. At least killing a boss feels epic in some sense. Farming elites is way more frustrating because you never know when some mob is going to spawn with some impossibly retarded combination of affixes. But let's ignore that. Let's say farming bosses is categorically off the table.
Ok, what does boss difficulty have to do with what they drop? Bosses could drop jack shit nothing at all and still be the hardest fights in the game. They should be some of the hardest fights in the game. Even if they dropped nothing, players would still want to beat them because that's how you advance in the game.
Also, it's so trivial to make boss drops awesome without making them farmable. Make them drop some one time use item (e.g. Alkor's potion in D2), or an item you can only have one of (e.g. Annihilus in D2), or only make them drop something the first time you kill them, etc. If Blizzard was so irrationally opposed to the concept of boss farming, there was still absolutely no reason to make the Inferno bosses absurdly easy.
Or they could have done something really awesome like make bosses get harder every time you kill them, or after you kill a boss for the quest, start making them spawn with bonus affixes, or make it so boss loot tables suck at first but scale up faster with Nephalim Valor, so if you wanted to farm them, you'd definitely want to get 5 charges of NV first (which turns a "boss farm" into "just playing the game for a while, and killing a boss at the end"), etc. etc. There were a MILLION awesome ideas Blizzard could have done here, and they somehow designed, tested, and sold the hell out of an obviously terrible and disappointing one.
Then there's the attitude of all the publicly facing Blizzard employees. As I mentioned before, they talked up Inferno like nobody's business. It was guaranteed to be super hard and it would be months before anyone could beat it. Turns out they were completely wrong because the top players just corpse hopped through all of Inferno, effectively skipping past all of the impossibly difficult mobs, and fought the ridiculously simple and underpowered bosses with trash gear.
Athene hit 60 24 hours after launch. Method beat Inferno Diablo in something like 80. Blizzard screwed the pooch. And instead of admitting they oversold the game and completely underestimated the ingenuity and dedication of their playerbase, and promising to make it right in the expansion, blue posts from the likes of Bashiok and others have been condescending and insulting, the equivalent of "Well that's how no life faggots play the game, but if you play it the right way it's hard, this is the best game ever and all of you are stupid."
Umm, Inferno mode was explicitly FOR hardcore gamers. You can't talk up Inferno mode for months saying how it's going to be the pinnacle of gaming challenges and then whine "that's not how you are supposed to play the game" when you get handed your ass three days after launch. I mean, you CAN, but then you'd be the idiots at Blizzard.
And don't even get me started on the auction house. (The interface, not the concept.) It's a fucking unmitigated disaster.
I could go on for hours, here, but I'm getting angry just thinking about all the ways I'm pissed off at how bad D3 is.
