The crux of the matter is that firstly the attribute system is too oversimplified and has very little weight on character builds and performance in combat. Seriously, compare D:OS & D:OS2 with other cRPGs like Baldur's gate, Icewind Dale, Neverwinter Nights, Pillars of Eternity, these games have so much going on in their attribute system than D:OS. Look at Pillars of Eternity, the most recent successful cRPG, they had an intricate system with 4 saving throws(Deflection, Will, Reflex and Fortitude) tied to different attributes and the attacks target different saving throws even for a Mage(different spells target different saving throws), on top of Damage Reduction against various attack elements(Fire, Corrode, Pierce, Crush, Freeze etc) and finally Resistance against different types of Crowd Control or Status Effect(Petrified, Burn, Poison, Disease, Knockdown, Blinded, Stun etc). Every attribute governs a different section of defense serving as the first layer of defense with DR and Resistance being the second layer but seperated into specific elements, players have to think when allocating points as every attribute is important, its not the matter of dumping everything in 1 or 2 attribute and ignoring balance.
Sometimes, simplification is not an inherently bad thing. Also different games work in different ways and aping what works for apples to apply that to oranges is not going to work well
Pillars of Eternity has a 6-character limit on the party. D:OS has a 4 character limit. That means that it's harder to fill all the roles in D:OS, and it would be much harder to be able to hit 4 different saving throws.
D:OS also has Memory to worry about, limiting pretty harshly early on what skills you have available to use. I can't afford to spend a slot on a skill which only removes one status effect, for instance.
The more different stats you have, the more numbers you have to try to keep balanced, which means the more numbers that will appear on loot. The more numbers which appear on loot and the more numbers you have to keep balanced, the more difficult it is to choose between different pieces of equipment which have numbers in different areas.
That leads to players eyes glazing over and them mentally checking out of the decision making process. This happens to me all the time when I try to compare equipment in games like Torchlight or Dragon Fin Soup. They have too many numbers and there are too many stats and so I basically stop caring about most of the numbers and just going for what roughly has the highest basic numbers.
Secondly there are just too many Magic/Int skill trees and that these skill trees are too good, they have the best balance of damage, utility and crowd control so much so that diversity and hybridization in D:OS series means picking a magic skill tree. For a start they should implement a good spread of Strength and Finesse skill trees to add to the current 3 we have, it'll give players more options and incentive to go into Strength and Finesse attributes. Furthermore skill trees need to be heavily specialized and not be like the current magic skill trees where they are practically Master of all Trades. Magic skill trees have too good of synergy with each other than with the remaining 3. It'll encourage players to diversify their builds instead of taking magic skill trees cos they can do everything.
TL:DR, If Larian wants to fix these problems, they gonna have to do an overhaul of the attribute system followed by balancing magic skill trees as they are currently Master of all Trades and finally adding more Strength & Finesse skill trees.
I was one of the people asking for stretch goals for a 3rd skill tree. Unfortunately, judging by the Kickstarter, it seems Larian was entirely uninterested in adding a third skill tree then. I can't see them adding one now.
At best I think all we can hope for is to make Warfare hold 24-32 skills instead of only 16 like the other sets.
More rolls is sadly something, some of us would really not want. They want a more chess like game.
But me for my selve, I really don't like, that putting points in only one stat is all you need. I would like a more classical approach like:
All attributes being useful for everyone would, as people have said, require a complete overhaul. It would either have to go to a Fallout-like - set at the start and be done - system, or else they'd have to give out far more attribute points per level than the two they do now. Two points a level is not enough to spread around in a system where all points have value.
In addition to this - just a spontaneous idea:
Why not implementing an exhaustion status (several levels) or stat that reduces strength, damage (possibly already included in strength penalty), finesse and maybe other, defensive stats - exhaustion speed depending on weapon type and armor type (or rather weight).
...
But maybe that tends to become a different game/system then...
Yeah, that does probably become a very, very different system.
