Personally I will be playing without Karmic Dice. I believe Larian's concept behind it is like the DM that occasionally smudges the rolls during a game. The game is designed around you failing rolls just as much as succeeding so I will take what the dice wills.
That said people did testing during Early Access and found that on average you ended up hitting and getting hit more often in combat with Karmic Dice enabled as it sort of evens out your rolls. So if that interests you by all means go for it!
Not sure if Larian managed to reach out to collector's edition owners but they said they would ship at the original August 31st release due to supply chain reasons. However the digital code to the game should have been emailed already ahead of launch.