First off, thank you OP for making the thread. Some of it has been discussed before, but it is an important (set of) issue(s) that should be discussed thoroughly. Perhaps we will manage to develop some good solutions, even if everyone has a slightly (or not so slightly) different view on the matter(s).
There's a couple of things to bite here, so I'll divide them into categories.
ACTING
I've mentioned it before, but I think it's quite over-the-top, at least at times. If possible, new, subtle animations would be great, add a lot of immersion and solve some of the "mime protagonist" problem Tuco pointed out.
SILENT VS VOICED PROTAGONIST
Imo the point is moot, as I'm pretty sure Larian have made their decision on this (and designed other aspects of the game with this in mind). If my understanding is correct, the protagonist (custom or origin) is going to be fully voice acted and they just haven't recorded all the lines yet. I do agree with those that say the budget could be used for something more worthwhile *coughdaynightcyclecough* and that it likely cripples the number of dialogue choices (especially choices that are for flavour/RP and result in similar NPC reaction/story path). I personally don't have the slightest need for a fully voiced protagonist in this type of game (apart from voicebarks perhaps).
Issues I've seen people raise:
1. Silent protagonist is bad. This has been discussed by me and Tuco as shown in the first post (for the current, voiceless state of the game) and, as I mentioned above, might be only relevant for (part of) EA.
2. Voiced protagonist is bad. Why? For some the voice is not what they see for their custom character, for others it breaks immersion in general. It brings other issues, as follows.
(Now as an aside I'd like to address something Sozz said - perhaps as a simplification, I'm not sure - that "blank slate" characters only serve as self-insert. I strongly disagree - some people want it for self-inserts, yes, but "blank slates" are just as much relevant for "really custom" characters - those where the player wants to handcraft all the background and personality for the character, not necessarily similar to his own. I'll leave "blank vs reactive" for another discussion, as it's a huge subject of its own.)
2a. With voiced protagonist, we can't expect much variety in voices for custom characters.
2b. Full voice acting results in less dialogue choice (as mentioned above).
Now, what would be the best way to solve these problems? In my opinion, it's to have the "basic" voices (those 4 custom + 8 origin) fully acted (as I suspect Larian are planning) and THEN add many (even a dozen or two!) voicebark-only voices with a lot of variety. Only needing to record voicebark lines would mean that a lot can be done quite cheaply and quickly. That would be, imo, a relatively good compromise that solves most of the above problems (with the notable exception 2b, unfortunately).
DEMEANOR
I pretty much covered the basics in my post the OP quoted. To elaborate a little on the implementation: what would choosing a demeanor mean exactly?
Suppose you create a character. You select the "sensitive" tag from the demeanor menu. It affects facial expressions your character makes in response to events/dialogue, as well as default and reactive poses, body language. These could be previewed in the character creation screen to ensure that this is indeed fitting for the character. (Example: "reacting to violence" -> shocked face, raised eyebrow or smirk.)
Perhaps several demeanor tags could be selected and put in priority order (one overrides the other if both could be used in a situation). A person could be both "skittish" (reacts strongly to sudden stimuli) and "violent" (expresses joy when witnessing violence).
What would it require of Larian? Adding several more expressions and poses. I'm not sure how much of what is there currently is a placeholder, but from my understanding, there's no such huge variety in the poses/expressions as to make it a problem to add some replacements. Currently a lot of animations is reused ("suddenly narrowed eyebrows").
PERSONALITY
This is more of the aforementioned "blank vs reactive" discussion, which also ties to the several discussions we've had on "Tav McBlanderson". A whole huge other topic (with several threads already). I have some ideas for having the cake and eating it too, but that's
an expensive cake something I'll leave for my Stupidly Long and Shamefully Delayed Post on Everything.
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Now to address some of the posts here:
I like the tag system from, I think it was in Pillars?, where you gained traits through repeatedly acting certain ways, I respect the attempt to incorporate a way to develop your character's personality this way; I wish more extensive systems like that were developed.
Yes. Tag systems can be amazing when done well and in-depth. Though for acquired personality tags there's the risk that the game will misunderstand your character. What I always bring up is a realistic evil character that will act nice 95% of the time. The game will "think" he's the best person in the world, while he was only nice because it brings benefit. Or simply isn't cartoonishly evil.
Only vaguely related, but I wonder if the game industry is already experimenting with Deepfakes and similar stuff.
Theoretically we already should have the technology to pick recorded lines, choose a new vocal timber and let an AI rework all your audio files.
Sure it probably won’t be perfect at every moment, but it could save an insane amount of money if refined over the years.
I'm impatiently waiting for it. Once effective realistic AI voice acting gets implemented, it's going to revolutionize the game industry. Well, at least the part related to voice acting. So much more variety can be had, the whole process becomes so much cheaper and simpler. Just a simpler "altering" (not "acting") AI for tweaking voice files (as you said) would be massive. I do think those technologies exist already and wonder when we're going to see it in games. (Admittedly, some potential for misuse exists, but let's be honest, people have access to this stuff already.)