Baldur's Gate III - Spoiler Edition (please read updated OP)

It's like DOS2, you can pick one of the characters who act as companions to be your character or make a custom one. In dialogues, there is a few choices that is generic to everyone, then some tied to the character, their race, their classe(s), their background and probably skills too.

All those characters have their own voice actors, the custom ones in DOS2 had a few voices they can pick from too. The VO is used for banter,  ambient auto-dialogue and when talking to those characters when they are NPCs/companions in the game.

There is too many dialogues choices and too many voice actors for each lines of dialogues to be voiced without making the VO budget larger than the rest of the game.

You could have made a custom character. That's basically why the option exist. Saying that playing as and having them as companions isn't the same thing from my experience.

For example, Sebille was an amazing protagonist while I can't stand her as a companion. I suspect the same thing is going to happen with Shadowheart and Asterion in BG3 (to me, i.e. won't be able to stand them as companion, will adore them as protag).

Bioware DnD adaptations have always focused on the combat character building. It ignored or altered a lots of combat rules that didn't work in RtWP, streamlined stuff a lot and didn't bother much with the out of combat D&D rules. In a way, they only focused on the player's handbook and ignored the DM's guide. They also tried to keep the players in combat as much as possible. They even use the Forgotten Realms as a generic low fantasy setting when it's very high fantasy in reality. The magic craziness is tame compared to the novels (I read like 90% of all the FR novels released, my local library had the whole TSR collection back in the 90s and I bought many of the later ones).

To many people that is how video game D&D is supposed to be: lose adaptation, good story, lots of combat and tame setting.

Larian seems to have took the manuals and tried to adapt 1:1 everything, even if in some cases they went with official variant for rules. See initiative, they use side initiative aka party initiative instead of individual initiative. I expect a lot more exploration, puzzles and weird stuff than combat compared to BioWare offering too. They also totally embraced the craziness of FR D&D with that intro. 

Now I'm seeing people complaining that they made the game for D&D fans or Larian fans instead of the BG fans and I'm all  . I bought BG1/2 because they were Forgotten Realms D&D games back when they released. I'm pretty sure the majority of the early adapters of BG were FR/D&D fans.

edit:
Another comment, I've seen many people asking for RtWP, but they only like RtWP if there is a scriptable AI that handle the companions: they want real time with no pause aka action combat. 

One of the expansion books: Volo's Guide to Monsters adds seven more player races:  aasimar, firbolg, goliath, keku, lizardfolk, tabaxi, triton, and .  Plus several "monstrous character" races like goblins and orcs and yuan-ti. So it's quite likely some of those may be available.

Although given vampire spawn is a playable race here, who knows what may ultimately be available?

Vampire Spawn isn't a race, it's the character background for Asterion. If you want to be a Vampire Spawn, you'll have to play as Asterion.

It's the ones that will be available for early access, there will be more for release.

5e doesn't have alignment restrictions anymore. You can have a good aligned cleric of Shar or a good Warlock with a Fiend pact if you want. Alignments still exist, but they are role-playing morality guidelines only.

”Good is a point of view, Anakin.”

So all the romances have sex as mandatory. That’s unfortunate, but I guess it’s good they at least said it from the start.

I liked DOS2 a great deal, so no reason I won't like this one...
But still, it goes a bit far into Baldur Original Sin.
The structure of the intro looks absolutly the same, captured on a ship, meeting your future team mates there, then crash in the middle of nowhere, gets reunited. Have to get rid of something (collar/ nasty brainbug) etc..
It also looks like DOS2.

Probably will be a fun game to play, I kinda wish they tried to make it a bit more different from DOSII though.
But I guess it would take way more time to produce if they started from scratch.

I want to complete the morph and play as a mindflayer

Perfect analogy by Delrith. Out of combat turn based mode is like XCOM 2's concealment mechanic. I think 2020 will be this decade's best year for gaming.

The first time I heard Gale I was pretty sure it was the British Male Inquisitor from DAI. Then watching all the BG3 stuff made me reinstall DOS2 and The Red Prince is the same voice actor (Harry Hadden-Paton).

I can't place Shadowheart though, but I'm sure I heard her before as well.