I'm on fort Ikon right now with my Witchblade and I will give the game some time before finishing, the high points so far were on act 1 and 2, act 3 as soon as you get to Homestead is boring as fuck. I had an overload of samey looking plains, samey looking forts and samey looking ruins, the setting is really well done but visually, Grim Dawn is alot less diverse than Titan Quest was. The first two bosses had some nice backstories but the act 3 three major bosses felt very generic and killing them wasn't as nice as killing the first two. I would cut half the areas of Act 3 as they are pointless and only focus on one boss with a decent backstory.
The sudden focus shift the game story takes from the Aetherials to the cult of C'thon felt unecessary, the cult of C'thon barely got any lore more than "We are crazy blood cultists!" and somehow it was boring to fight them, they should be expansion fodder. Maybe the cult approached you claiming to help defeat the Aetherials but they backstab you and you take your vengeance on an expansion, right now, I'm feeling "eh" and without much reason to care.
I don't like too how plenty of times NPCs send you to kill shit alone that their fucking armies can't. Some guy that barely knows you just see you and after rescuing you from death, just send you to single handly kill and undead horde and right after that " You go kill the fucking guy that is sending those undead armies, alright?Easy shit tha any nobody that barely escaped being hanged can do." I know that Diablo 2 clones are about killing shit and earn better and better loot to kill shit and to many, story is optional on those sorts of games but Grim Dawn has a post apocalyptic theme to it and a pretty good setting that could be used on more interesting ways, you being asked to do shit that whole armies can't without any care for hiding you are playing a game is disappointing and lazy, epic heroics and a post apocalyptic setting felt weird to me.
On Diablo I, you are only one of the many adventurers that seek money on the Cathedral, people don't place too much faith on you and they have no clue what is inside, on Diablo II, you seek a lone wanderer while being guided by some crazy old dude.
The setting is pretty cool, the lore well written, the story is some cobbled together shit where no care was placed on, the low variation on the enviroments can induce boredom especially on later acts where the epics are dialed up and the story gets less and less interesting, theorycrafting a build is pretty fun. Grim Dawn is a run of the mill Diablo clone, I don't know if I can say it is better than Titan Quest as a game, it is more interesting as a setting though. I found Torchlight 2 gameplay to be more engaging.