Was looking forward to Stalker 2, but that's been delayed to Q1 2024.
Having played all 3 (but not completed BG3 yet, so YMMV): the 3rd is indeed better than the first 2, the bar was high, they went over and beyond. (edit) and a lot of BG1&2 celebrities are back. Jaheira, and I hear Boo&Minsc too.
I'm 170 hours into my first BG3 play though and while I might give it another one at some point, I don't think BG3 will hold my interest as well as the first two games (which I've played through a half-dozen times, and thousands of hours, each) have. The BG3 narrative is much tighter in some areas, but polish is oddly lacking in others. Voice acting in the original games, especially among the antagonists, was noticeably better (hard to match the likes of David Warner and Kevin Michael Richardson). The original games were also notably less linear and more open, especially the first game, which is something I appreciated; not everything needs to wrap back around to the main plot.
Regarding the returning characters,
I've recruited Jaheira and Minsc (with Boo), and encountered Elminster, Sarevok, and Viconia, but their stories all seem relatively minor compared to the other recruitable characters and a fair bit of retconning was required to mesh them with the current plot. Notably, all of them are far weaker than I left them at the end of Throne of Bhaal (though it would be very hard to have a game were this not this case as any one of them would already have foiled the Absolute plot), despite the timeline advancing a century, while most of the character development that happens with Viconia and especially Sarevok seems to have been discarded entirely. I think the game probably would have been better off without most of these cameos.
I never got around the magic system. Picking spells for fights you have no clue about. In the table top I ignored the preparation crap, casted what I wanted and had learned only limited by the slots to tell me how many rank X spells I could cast.
The Vancian memorization/preparation system encourages forethought and is a critically important limitation on the power of spell casters, especially in earlier editions of the game. In AD&D (1e and 2e) for example, it takes a high level MU/wizard about a week of game time to change their complement of spells, which was a limitation I religiously enforced. Indeed, aside from loosen the arbitrary and ridged spells per level caps (I did move to a spell point system to add more flexibility to what spells could be prepared), I was careful to enforce every rule that made life more difficult for Wizards (I was a stickler for spell components, memorization limitations, item saving throws, attacks of opportunity, rest periods, etc and so forth)...and they were still the most powerful class in the game, pretty much from the get go (
charm person, a level one spell, is phenomenally potent in the earlier editions, for example), by a mile.
Even in later editions, where they increasingly poured on the psuedomagical/supernatural powers for traditionally more mundane classes, wizards and (to a lesser extent) priest still had a slew of abilities that no one else could duplicate and keeping them from being able to dump a tailor fit complement of spells on a single unanticipated encounter is an important balance consideration.
In video games, where wizards are mostly reduced to magical artillery and priest classes mostly healers, it's easier to ignore these limitations without breaking things.
Is this preparation thing still in BG3?
You're able to alter prepared spells any time you're out of combat, with no need for any rest period.