Here's an interesting article where Greenwood lays out some of his general thinking on the subject. It's from the October 1981 issue of Dragon Magazine, so keeping in mind that it's 40 years old, it still has some choice insights from the dude who first invented the Realms. The relevant section starts on page 8
I'd say what we need is a simple primer, at least for the Greater Gods listed, the ones who hold sway particularly in Fearun, if not the whole of Toril. Also the lesser Gods or demigods that have since been promoted to more prominent positions in the lore or who the game intends to focus on. Again that article is pretty old hehe.
Sure a complete and exhaustive treatment would be a bit much to ask for, but I still think they could do something that captures the broad sweep. Just so the new player can get a bit more situated, with a better appreciation of the scope and relevance to the setting. I don't think I can really assume that the average player will have the same interest in comparative mythology or religion that I might, but a good creation story could probably do a lot of the heavy lifting. We probably don't need a whole Theogony where highlights version would probably suffice. More detail can be explored if the PC chooses to play as a Priest, where additional insights can be gleaned along the way. I mean Silvanus gets a brief mention as being "thorny" from Zevlor, and we know the druids care about that one, but I think part of the issue with most of the other gods stems from a general lack of temples and priests among the NPCs in the EA game. We don't start in a town or a city really, so I suppose it makes sense we don't see much, but still seems like they could do a bit more in the initial presentation.
Just as an example, BG1 the treatment was relatively sparse, granted, but it did introduce Bhaal as a central focus with a fair bit of narrative support there. Basically they used the Lord of Murder as an in for the newcomer PC, even if they weren't particularly concerned with the broader divine tapestry, that part of it was unavoidable and it had some set up. In BG2 FR religion was treated a bit more like pop up mega churches with a North American slant (thinking especially of the temple district and the unseeing eye subplot). A lot of the time it felt like more of a send up of the FR religions and more comedic, but it nevertheless carried on with the Bhaalspawn thing as central. In this game, where we still don't quite know what the Absolute is meant to be (perhaps it's an extension of the same?) I think they could still do some setup for the Shar/Selune thing. Especially since FR departs a bit from more familiar treatments in real world mythology. Here it's a more Manichean dualistic take of opposing forces, as opposed to like the triple goddess take with 3 phases of life, waxing and waning, that we get from more familiar source material. Here we have the moon in opposition to itself, as opposed to being in opposition to Sol Invictus, or like a calendar conflict or compromise between the Lunar year and the Solar year. Since it's fairly different in FR, I think that'd be a good place to start.
Shar is presented as a Greater Goddess in that list, with the obvious analogs being Kore/Persephone in her aspect as Praxidike (judge and ruler over the shades) blended with Hecate or something more protean and witchy, malevolent and cruel. Basically Darkness writ large. Selune by contrast is listed as a lesser goddess, with the obvious analog being Selene/Diane or Phoebe/Letona. If Lathandar is Sol Invictus, and Selune is Luna, then Shar is basically Nyx like the black night. More primeval. But the Selune vs Shar conflict has graduated (over various iterations and here too it seems in BG3) into to something a bit more central to the story. So I think they could play that up with some payoff, and maybe just cameo some of the other players? Honestly I don't know what it would look like, but I don't think it needs to be crazy long. Again like anything more than 3-5 minutes and the player is tuning out probably. Unless it's an edge of your seat 'kick this into overdrive' thing like the opening cinematic lol. But I doubt we get another one of those. I'm curious if chapter 2 or 3 might have such a mini featurette to set the stage? But I think they were probably eager to show off their best of the best in the trailer, so I don't know if they are cooking up anything more at the scale, except perhaps for a finale climax maybe?
Anyhow the big list of the FR gods on page 10-11, and the follow up breakdowns on pg 52, all seemed like they could be worth mining a bit more and use some of that to deck things out a bit in BG3. I also found his motivations for doing certain things pretty instructive. Like at least it's probably a good read for the historical curiosity even if nothing else heheh
