Quote Originally Posted by Ionathus View Post
I'm actually introducing my players to Athkatla right now: they haven't met any characters from the game, but the setting and the map and the organizations are all the same! It's been very, very nice to have them say "okay we want to go to the poor part of town" and I can say "why yes I do just happen to have a photographic memory of every detail in The Slums"
Cool!

Your rules changes on the whole look pretty good. I don't think you need the HP nerf - I'm running a high-level 5e campaign right now and I can threaten the characters' lives just fine even when they have high HP values. Keep in mind that a Fighter in SoA:ToB could end the game at level 40, so the HP nerf was more necessary, but you're only going to level 20 (in 5e). The players are going to need every hit die by the time they're facing multiple liches, dragons, Demogorgon, etc. A single Meteor Swarm is gonna chew through that HP in the blink of an eye.
I just finished a high level campaign and it took a lot to threaten them. Looking ahead at the higher end challenges, the only time they face a bunch of really tough opponents at once are some of the fights where there's a half-dozen high CR devils/demons/Slayer Shadows running around. Even Fire Giants are only CR 9, and a 15th level party can probably handle 4-6 of them at a time with ease, with the giants likely to only hit once per round against ACs in the low 20s (excluding Shield, Haste, fighting styles, etc.). Especially at the higher end of the game, I suspect we won't see as many encounters per day as at lower levels. For example, Yaga-Shura's lair is kind of boring with a number of same-y fights and very game-like token collecting, as an example, and I'll probably have to alter/shrink it.

Careful with the named NPCs. They're likely going to be precious and interesting to you, but you have no idea whether the players are gonna friggin' hate Yoshimo and Imoen and instead hyperfixate on Ribald Barterman and ask him to come with. My advice is to keep them in the background, make them quest givers and occasional guest team members in a single fight or two, but mostly let the party determine its own dynamics.
I feel like having a "you can bring one NPC along" option means that they can choose to fill any holes in the party dynamic, and if someone's out, they aren't missing 1/4th of their combat power. Nobody will feel like they have to play the cleric, wizard, rogue, etc. if they know they can grab an NPC for whatever role they want.
The BG2 NPCs almost all have some kind of quest or quest hook associated with them to flesh them out a bit... but it's going to be up to the players to bite or not, and whether or not they are interested. It might be interesting to see how they handle, say, Keldorn's side quest with his family. Very much story, not combat, there.

Don't involve Imoen in the main storyline - give them another reason to care about Spellhold.
Finally, and this is the only big one that I think is going to make or break the game: just friggin' make them all Bhaalspawn. Nothing in the game or the story breaks if you just say "you all grew up as orphans in Candlekeep, raised by Gorion, who was then slain by Sarevok, and you found out you were the children of the dead God of Murder just like Sarevok." Jon Irenicus and Bodhi can steal multiple souls each, why not, you get to make the rules. It makes just as much sense to say "yeah the grafting process doesn't give them the full power, so they needed multiple bhaalspawn for the ritual" and then everybody's got a Stolen SoulTM. There are so many Bhaalspawn running around in ToB anyway that it makes just as much sense, and then you both A) don't have to jump through any hoops to prevent a few characters from becoming Main Characters and also B) you have a very neat, very simple way to keep the party together.
At the end, do they have to vote on who becomes a god, or does it turn into an intra-party murderfest until there is only one left standing?
When souls are stolen, do you have an entire party that can turn into Slayers? It's an evil shift, but they will be able to mulch anything in their path.

I may leave it open for "alternate Bhaalspawn" as a choice for everyone. If I do end up with several Bhaalspawn I will drop Imoen.

I think some of my players will have more fun with the dhampir origin, or getting some 2e-style semi-random psionics (which they may remember from the early 90s), or the other options that don't put as much stress on them to have to have a character with a big dramatic internal struggle going on.
It's D&D... the players get a big vote in what happens, and I really don't know what they will choose.