Production issues aside from Panel From Hell II, based on Swen's comments about adding offices and staff, I truly believe Larian is underequipped and understaffed to implement everything this game requires effectively.
Patches are taking longer because they aren't able to de-bug and program quickly enough even with their already tripled headcount from 2017. It still isn't enough and it shows in all the delays with every update and the lack of a clear timeline.
With everything else that needs to be added to the game, there is just no way Larian is going to meet a 2021 release date. They might still be missing classes and subclasses for EA at that time.
They are severely overwhelmed with this project and didn't anticipate all of the demand required to execute this successfully. I am worried they will start cutting corners sooner or later to satisfy Stadia and other commitments.
I believe Larian would need to hire over 100 more people in order to get things back on track. There are a lot of issues that we are just not aware of and most of it comes from the fact they just don't have the manpower.