Well, that "real SH" you want to talk about is entirely dependant on what any individual player does in their game. You may make her "good" in your game whereas I may make her "super-evil" in mine. So exactly which of those is the "real SH"?
The only SH we all can talk about and make observations about is the default SH that Larian gives us, the SH as she is when we first meet her. And that SH, as a Sharran cleric, is evil.
The real Shadowheart is the one that is in your, mine, or any other player's game. That's the beauty of it. You can stick to the character sheet if you want, but other players are looking forward to shape Shadowheart's character based on their actions throughout the game. You may have your preferences about joinable characters and that's fine, everyone likes different type of characters. Do I miss some more characters? Hell yes, we don't have a dwarf or any representative of short races for that matter. Nobody will be fully happy with Larian's set of characters they offered in B3. You are not happy, I'm happy (not fully maybe, but the cast looks at least interesting) and that's the way it is. You cannot please everyone, and if they'd try that, this game would be a failure for sure.
I could use one or two more good-oriented characters, but definitely of a more ambiguous story (like Keldorn), rather than a straightforward, unrealistically presented beacon of good (like Ajantis). And to be honest I'd be scared to play a properly implemented lawful good paladin, because those tend to be zealots, who doesn't care about collateral damage in their desire to purge the evil from the face of the world. I've seen a good bunch of such disturbingly written characters in Pathfinder: Wrath of the Righteous. But if such a zealot paladin would be written in style, I would not exclude playing an origin like that. It would be a new territory for me, something I always like to explore. I'd also welcome such a companion i my party, especially if there would be a way to straighten their views more to a good part of his alignment rather than lawful (which I believe is the root of their zealotry). I won't look at companions like just a character sheet, with just class, stats and alignment, but I'll try to shape their story however I find suitable, sometimes even straying from what I would do in RL. I think this will be the most fun part of BG3.
