1) Companions will interject a lot, and I mean A LOT, but won't directly act against each other in quests or anything. The party ultimately still defers to you, the devs aren't going to randomly have a party member leave just because you had two specific party members have a disagreement at a specific point in the game, and you ARE the party leader, after all.
2) One would argue that evil characters may be MORE rewarding than a good run. Lich mythic path especially has more secret companions than the rest as far as I've heard. It doesn't clash with the narrative at all, it'd only somewhat feel awkward in the first two chapters for obvious reasons.
3) Honestly? The crusade system when I played in beta was rather interesting, but I felt it was sort of an afterthought in terms of development work done on it throughout the entire testing period. I am hearing of some concerning bugs and possible balance issues involving them right now... I honestly hope the next game ditches all of the management stuff, because it's clearly not the strength of these games.
4) No one has really gotten that far enough into the game to know, besides the few special people hand picked to take part in closed beta of the final two chapters. I cannot give a fair assessment as I am playing on normal difficulty either, but most people seem to agree that Core and above is bullshit and poorly balanced. It's largely going to depend on what you're really looking for in this game.
I could say that my rationale for enjoying WotR is mostly for the writing (especially party banter) and character customization, and not for the balance. Probably ironic considering how much I care about BG3's balance in comparison, but at the same time, my approach to BG3 is that given Larian's prior development history, my expectations around it are that BG3's combat is literally the only thing that I really care about. Everything else about the game in their current state is just a bonus to me until Larian can show me that the companions are somehow going to evolve past the limitations imposed upon them by the origin system.
Thank you for the answers. What I was looking for back when Kingmaker came out was an original BG-like experience, and what I got didn't exactly sit well with me in the end (it took me until last year to try to get into it again after my original playthrough back in 2018 died to bugs that made me unable to progress the main plot). I expected the combat to be challenging (I absolutely adore D&D 3.5, and like the fights there), but in an interesting way - with enemies being strong but not to the point of your best martial characters hitting them once a year while taking hits like nobody's business with 35 or so AC. Kingmaker on Challenging both in very early and very late game felt like armor and shields barely mattered as your melee fighters melt anyway, and most of the low-level spells just didn't work because enemies went past the HD thresholds pretty much immediately, while the top-tier ones were negated either by spell resistance or insane saves.
Kingmaker's combat didn't require tactical thinking in my book (in turn-based - even less so, I tried doing a run of Beneath the Stolen Lands in turn-based and after a while I just started repeating the same optimal actions on characters in every fight) - just a combination of understanding the system and the game not screwing you over with enemies that have 30+ Strength critically hitting your fighter for over 100 HP and killing them in one hit. Or, in the middle part, just spamming enemies with bombs and fireballs. There are no tricks, no cool approaches - a suboptimal party will suffer to an insane degree while an optimal one will also suffer, but less so. You can't summon a Mordenkainen's Sword to clear out all the illithids without breaking a sweat like in BG2, for example - the spell selection is very limited and there are way too many transformations that are freaking useless for the most part because their parameters are not balanced properly, but not really any actually interesting spells. And with how much combat there is, it became stale for me pretty quickly.
And character customization is nice and all, but when many features either don't work (bugs) or barely differ between classes (the tactical leader inquisitor and vanguard slayer's trademark ability, for example), it also turns into just picking the one actually functional combination of feats. Them just mindlessly copying them from the rulebook, sometimes without even adapting the description (which makes no sense in the game), also led to there being, say, weapon proficiencies for weapon types that don't exist in the game.
That was about enough venting, I think. Thank you again.