You CAN play your own custom character with or without the NPC companions.
You CAN choose to play as one of the origin characters. Probably more characters will be coming.
You CAN choose to play either custom characters or Origin pre-made characters with friends, or for example 2 custom characters and 2 pre-made characters, etc.
You can do literally whatever you want. I don't understand how having all these options is a problem?
I'd like to play as a character who has ultimately more ties to the core plot of the game than her companion NPCs, and/or a legitimately sensible narrative for why all of these amazing, special individuals unanimously all agree that she should be the leader, despite her being functionally nobody with virtually no adventuring experience. Can I do that? Not currently.
I'd like to play a game where not having a particular companion doesn't end up either locking me out of an unacceptably large portion of the game, deny me legitimately reasonable options that are only available to the 'special' character, for no actual reason, or bring me to an important
part of the game and act like I should know a lot more about things than I do, because I needed that character, arbitrarily, to access the information, with no other possible recourse. Can I do that? Not historically in Larian games, and they've made no sign that it won't be happening here as well - and there are signs, indeed, that they're already trundling away into the same old traps as before.
I'd like to be able to play a personal character of my own design, and not spend the entire game feeling like I'm functionally experiencing Less
of the game than I would be if I'd agreed to give up my own character in favour of filling the role of one of Larian's special darlings. Not a big request, also not looking likely at this stage.
I'd like my character to feel like part of the party when we adventure, not some mute drive camera that is moving the others around so that they can chat with each other and ignore her. Can I do that?
I'd like to have party conversations where my character is one participant amongst several, and able to contribute meaningfully along with the others... Not being the stand-in fall person whose only job when talking to companions (or, indeed, most non-party NPCs) is to say stupid things, to be ignorant, or just plain to feed them the required line they need so that they can condescend to her and show off how special they are... In the data mining, of course, played-as origin characters all have lines that let them get the better of many inter-personal conversations, or to come out as the superior one... but the custom player character does not, in almost any circumstance. I'd like to play a custom character that actually is permitted to feel at least somewhat like an equal in the group that they are supposedly the leader of. Can I do that? Not currently, and things aren't looking good for this changing.
So many elements of this game have been designed in away that dismissed a custom player character, or were clearly implemented by people who were only thinking about playing one of the origins, and it shows.. and it continues to show, each update.... so yes, I'm feeling pretty jaded about it at this stage. There is a LOT to like about this game, and a great any things that can be enjoyed and things that look neat, or are done well, but there's an equal measure, and and overbalance besides of incredibly poor decisions and design choices that drown it all out.
I'm glad you're enjoying the game, and I'm glad the weight of poorly designed, badly implemented and ill-thought-out elements haven't gotten to you yet. As you say, some of us have more experience with Larian's games than you do, and many who do can already see the writing on the wall very clearly.... and are suitable concerned and worried by it, which is why many are being very vocal now, rather than waiting until release to complain.