But really, Larian didn't advertise any kind of scripted companion so far in any manner, unless I miss something at some point in time.
The characters are all going to be originated from the pool of Origin Stories, meaning there won't be any specific, handcrafted companion *at all*. There will be premades I reckon : class and race will probably be set in stone, like, Origin Story 1 is a warrior redhead Dwarf named Maximilian, OS2 is an archer blond elf named Legolass, OS3 is a mage brunette human named Raven, etc. ( all tremble before my mighty naming imagination ! )
The most handcrafted I can imagine to be beyond that is that the writer will probably give preference to answer A from origin story 1 in a certain situation while origin story 2 will prefer the answer C in the same situtation. Thanks to Love and Hate I expect this to be a bit more organic in nature, like if origin story 1 hates you, he will rather choose answer B whereas should he like you, he will go with A.

SP is probably going to not feel very much different than MP except the answer of the companions will be preselected by some writers magic rather than by another brain somewhere else in the world. As a player, you will still get to select your answer and watch what the other characters think of the situation. Only difference will be that you won't control the full party in MP.

Since this is how I expect things to unfold, you can easily understand why I'd say "please, don't force us to play a warrior dwarf as the Origin Story 1 companion, maybe let me at least choose his sex/class, and better even his race *if applicable*. If we can in MP, why couldn't we in SP ?".
It may then be way too complex to give a weight to each and every possible answer coming from race, trait, talent, and origin story, so ultimately choosing to create your own party member would simply lead you to having to assume full control of the character yourself.
Should you choose to pick the premade character though, well then, you're in for the standard companion action.
- You want your own custom team, create 1 to 3 more characters, and assume full control of them.
- You want scripted companions reacting by themselves to your actions and to the world, pick the premades.
Both type of players will have the same experience regardless because in the end, everyone pick a story from the OS pool. And neither solution will diminish in any way the work of the writers. One player will get something more unexpected as the scripts will play with/against him, and the other will get to see the full range of possibities.

It's really just a different take on things and none are less valid than the other, regardless of what I may think of 90% of the companions in cRPGs.
Because, do not get the wrong idea : I still see as perfectly valid the fact you like playing with prewritten companions. As I think I said, that's how I do my RPGs too. If given the choice, though, I will ditch them in subsequent playthoughs. DOS1 was actually the first time ever I immediately ditched the companions by going dual Lone Wolf. When I did BG:EE recently, I immediately formed my full custom party because I already had a go at the companions years ago and didn't want nor need to have them again with me. Sorry, Minsc and Boo! And this has nothing to do with the fact they are well or badly written : it's more about how well they contribute to the flow of the whole game, storywise as well as gameplay-wise.

The Brotherhood of norD is love, the Brotherhood of norD is life.
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