I've started playing this after wrapping up my first complete playthrough of the first Pillars and so far it is really impressive. If the bloom doesn't wear off too quickly I believe it may be the new reference for isometric CRPGs (and a strong contender for Divinity Original Sin 2 especially if you prefer real time with pause to turn based combat).
For the record I had a hard time getting into Pillars because of the constant patching and balancing/nerfing which made me restart a number of times without going much further than the second Act of the game.
I do prefer playing Rogues and in the first Pillars they are the very definition of glass cannons which means that you have to come to terms with the fact that you need to hide behind meatshields in order to avoid taking dirt naps in every other fight. Of course the fact that pathfinding sucks (in the first Pillars, they did reduce the size of the party down to 5 in Pillars 2) and that combat focuses on engagement (and opportunity attacks) really didn't help the Rogue to move around the battlefield.
It wasn't until I started playing a Barbarian that I found a main character that had some lasting power and gave me something less vanilla than a plain Fighter (I'm not hating on Fighters but in most games of this genre they are just the dumbest class to play). Of course given the Pillars ruleset you have to come to terms with the fact that Barbarians require high Intellect to be effective (they do minor area of effect damage with every successful attacks and the area is directly tied to the Intellect rating) but that's hardly something that would come in the way if you want a main character who is a bit smarter than the rest.
Another funny quirk of the Pillars rules is that Might does modify damage regardless of its type. So both weapon damage and spell damage are modified by Might. Might even applies to the damage done by guns which does sound weird. Bottom line it's best to accept that for what it is and consider that many D&D features didn't make much sense either.
In any case I'm straying a bit from the matter at hand. Truth is Deadfire does build on the first game but with a lot more clarity and efficiency and that's a relief (story wise it makes a lot of sense to have played the first game though especially since you can import your old save).
There are so many additions and improvements I could write another wall of text just trying to list them and I'm still in the opening area of the game.
Bottom line, I haven't been so pleasantly surprised by a game since Divinity Original Sin 2 (especially considering my expectations for Deadfire were just a notch above the first Pillars game). I certainly didn't expect Deadfire to look anywhere as good as Divinity Original Sin 2 but they've managed to achieve that.
I'll have to see how the game lives up to my current expectations which are now much higher and I'll have to report back after playing ten hours or so to give a more informed opinion on the beginning of the game.