just some theorycrafting -
i think if larian introduced a mini prelude to the actual event or scenario that has you scooped up by the mindflayers then that could be a good opportunity to introduce some tutorial like mechanics, like dialogue rolls, movement, camera control, and trading, and also answer some questions regarding what your character was doing before they got thrown in the mindflayer pod - i envision that as a player you create your pc (not your dreamer quite yet tho), after which there is some minor narrative dialogue/power point like slides related bringing the player up to speed on the world of FR/BG (like the recent avernus debacle and what the dukes have been doing in response, etc) and using your selected character background to make the prelude more personal along the lines of youre a soldier returning to baldurs gate, or you are a sage traveling from candlekeep to the gate, etc. (obviously more 'out there' character concepts would need to be more finely tuned) but in such a mini prelude you would then get a really limited snapshot/tutorial of BG (or yartar or wherever you get picked up) that would give you a chance to also purchase your starting equipment.
im envisioning you dialogue your way through BG front entrance flaming fist, have some opportunities for some minor dialogue with some BG refugees to give some added FR atmosphere, you get to talk to merchants/quartermasters at the front gate area where you can select/modify your starting gear, and once that merchant dialogue ends the mindflayers attack and you go from there and create your dreamer once the trailer gets back to the tadpole administration moment - i think it would be an easier phase in that jumping right into battling imps and mindflayers in the seven hells
(also tangential, but i would think that a lvl 1 character would have a much harder time battling imps in hell on a planar spaceship - unless the devils are in on it? but that theorycrafting gets into larians plot that we dont know the full details of as of yet)
