Obsidian just posted a second update on YouTube further discussing the new multiclassing features in the character creation system of the upcoming Deadfire. As Josh Sawyer humorously alludes to past Bioware game's multiclassing pitfalls, you get the feeling that they really do understand those of us who get what "Role" means in RPG and that half the fun is character building and development.
Since I've been asleep at the switch for the better part of the year and haven't posted anything in awhile, we missed out on part one, thankfully YouTube is there to archive such stuff:
Deadfire Update 7: Multiclassing (from February)
Deadfire Update 40: Multiclassing Part 2 (just posted)
Apparently during the initial testing it was found that it was still possible to, as Josh puts it, "create a non-viable character..." so they had to further tweak the character development system to aid the player in making wise decisions when building a new protagonist.