Your critisism has some merits, I also have problems with being immediately in the middle of everything or the saviour of the world. For example I never could accept being the person in PoE2 (I did not play PoE1) and following a weird god while exploring a Caribbean holiday area. Or being the Dragonborn in Skyrim or a searching farther in Fallout 4.
On the other hand the design is partly the fault of DnD in general. The "heroes" of this universe are very quickly super beings who mainly do the big stuff, sadly. The setting you describe for BG1 sounds bucolic but how can a group of nobodies become semi-gods over the small timeframe a game takes place? Which they do. That's actually nonsense, more nonsense than to be accompanied by a vampiric elf and been confronted with mind flayers at start.
Obviously the mind flayers are not the main threat of the game, at least I hope so. They are overused as "the enemy" and boring, and that's of course also the "fault" of earlier good games which used them. BTW I never had to confront a mind flayer in the game, it's maybe bad design to have them in the tutorial on board of the ship, but it is also bad gameplay if the player tries to fight them (or get Everburn) instead of fleeing from the ship.
It's too early to judge about the story. It could become very good or a total desaster, depending on what is in the background and why you are there and with such companions, and what is to be done. Maybe there are reasons beyond randomness for certain events and setings? Ok, judging from the experience of D:OS2 I haven't the highest hopes or trust in Larian that we get an ingenious story, but let's wait and see. It's certainly easier for me to say that and wait because I don't have nostalic BG feelings and prefer turn based combat absolutely over the messy rtc stuff from the earlier games or competitors.
