Well, the biggest issue I found with Darksiders II is Death was very underwhelming, as a Horsemen.
War, stripped of all his power, was intimidating, fierce, and believable as a power. Death, stripped of his power, was like a child. He put on raggy pants he found off LV1 Enemies...LV.1 enemies could infact kill him. Also the fact is, Death was stronger than War, regardless of power. The leveling stuff also is stupid when you consider this is the Grim Reaper; whom has taken entire worlds, and people of all creation fear him. But a generic, LV.1 Enemy can beat him.
The game wasn't hard, if that's what you take from what I said. But the fact is, making it more RPG was a bad idea. Darksiders 1 was an ARPG, much like Devil May Cry / Zelda. It worked. Adding levels, random loot drops, shops, and such, ala Diablo III was a mistake for a series like this.
I couldn't suspend my disbelief at how pathetic Death seemed. Not to mention the comics said he was cold, calculating, didn't talk much, but was very mature. Well mannered, even. In Darksiders II, he seems young, immature, he trash talks, and he asks about stupid stuff that anyone would half a brain cell would understand. War didn't talk much...but when he did, you really "felt" it, he played his Character well. Honor-bound to the core. A great rage inside of him, always bubbling. He was War made flesh.
Also annoyed they decided to make them the children of Angels & Demons. I mean, it's an old concept, yes, but the first Darksiders had them as an Ancient race, the first God created, destroyed internally. Immensely powerful, made more so by the Council. Now they're just the children of Angels & Demons and don't exactly seem nearly as impressive or unique.
Darksiders 1 was rough around the edges, but I found it incredibly hard to put down and thoroughly enjoyed it. Darksiders II had me incredibly excited...I had seen videos and thought it might work...but no. Gear dropping from almost every Enemy, 90% of it being useless..the addition of towns, vendors, NPC's, and minor quests out of something like Skyrim. The massive amounts of back tracking and the uninspired enemies. A game like this should be 10-12 hours, at best, as was Darksiders 1.
The characters, gameplay, and locations aren't exactly that exciting and get stale quick.