So I Hated party control BG1/2 ... A lot did when it came out. To much point click dragging on the screen and the pathing of the characters was horrendus in the first game.. It was a meme how many times you clicked form one side of a map to another and and Minsc (with speed boots) was the only one there 5 mins later.... That is why "You must gather your party before venturing Forth", is Iconic.. Cause they never pathed to where you told them too.. So go click them solo and get them to Minsc...again.. While that spammed... I guess you haven't kept up with the times in the last 20 yrears so here are some answers to your questions...
1) Baldur's Gate 2 ended.. Dramatically.. So depeding on your playthrough, You became a new "good" Divine or embraced your father and became Bhaal... The End..
100 years later .. New threats on the Sword Coast yada yada..
2) I think you may be confused with what "Early Access" means... Wizards don't cast divine spells.. It's called a bug. I agree a solo Sorc playthrough maybe viable though.. Same as BG1/2!!
3) BG1/2 EE are up to 6 in a party. I loaded my game up and checked not 4... BG3 is yes, the change came with it now being D&D 5th edition. In earlier editions larger parties were sometimes needed because classes were more specilized. In 5th, classes are far less restricted and less are needed to fill roles. We dont need lockpickers or just a spellcaster or healer.. Every class can if the right feats, skills, and/or speacialty are picked.
4) Rolling stats is not a signature of Baldur's Gate.. It is of D&D since the 70's. The point buy system is official Wizards of the Coast Dungeon League rules though... Larian has said the are working on getting a "roll" option.
5) Nope its called "Science" wierd huh..
5b) I think you should try different strategies.. Jumping takes your bonus action.. Bonus Action can be used for more BACKSTABS if you Duelwielded!!! Even Wizards with a off-hand dagger can cast and then off-hand stabby stab

All classes can Flank, giving advantage.. This isn't 3.5. We do need a jump quit slot button though, but early access. Not all features are in the game yet, and others need to be tweaked.
6) Yep, dice rolls. It's what makes you really feel like you are playing D&D. I agree, and posted about to many rolls for the same outcome is bad DMing. It is when there are multiple outcomes, which there are in some cases that there should be multiple rolls. We should't have 3 rolls to fail. With the same positive outcome.
7) Who told you there was no Minsc and Boo? Have you searched Baldur's Gate yet? I know he was just brought back from a stone statue.. Also take that rapier out of Wyll's hand and give him duel +1 daggers.(He can duel a torch main and dagger offhand too

That gives him a Bonus Action Attack with his offhand. Hex>Eldritch Blast- rd1 >Eldritch Blast> Offhand Stabby Stab=1d6/1d10+Cha/1d4+1 :O Over 20 damage! The Wiz Gale is decent at this too! Yeah the companions are just about some of the best I have ever seen.. Way better than -Imoen's “Whatcha want?” 1000 times over everytime you have to forcibly make her search for traps after reloading again...Its sooo nice just to get closs to hidden objects and things and rolls auto happen without you having to do anything...
7b) D&D 5e has been out for awhile now so you might as well get use to it.. All Classes can Heal, Dps, Disarm Traps, Cast Arcane or Divine spells at some degree. Yes you can be a Druid lockpicker that cast Magic Missles and wears heavy armor before you shapechange into a T-Rex to eat your foes. Play your way. Hopefully coming to EA soon.
8) A day and night/weather cycle would be nice. It's still early access, it may be in the works already.
9) The Flaming Fist is a band of "Mercanaries" that are now the Military and Police of Baldur's Gate after the last 30-40 years of losses to Chult. They wear all kinds of armor. Based on class..
No standing army is rich enough to outfit everyone in plate.. Half of the Fist are Rogues, Rangers, and other classes that don't wear plate because it restricts your Dex.
10) Completly wrong.. So Baldur's Gate 1-2 and now 3 are all completly turn based. First two are Real Time with Pause, the other Turn-Based Pause. It is a evolution in turn based combat. Both are based on D&D turn based combat. Your characters in BG1-2 only made a few attacks per turn, and you pause it on your "turn" to assign actions... It is just how you control the pause that changed and made it more tactical. Games wish they could look this good 20 years ago... It's like looking Atari games and going.. "oh man games were so much better back then with one big red button". Thats your opinion...
Let's not forget that a lot has happened to Baldur's Gate in the last 100 years. The last Bhaal Spawn ascended in BG2 Throne of Bhaal. This is what is happening to the city 100 years later...