Subject to patches, a few of my favorite WotR things, beyond "Oracle Angel" and "Melee Lich" stuff:
Leveraging Elemental Barrage the Eldritch Archer becomes an absolute monster. Build is a bit fiddly and feat starved because of spell resistance but the aim is lots of arrows with all three elemental weapon imbue's active to plick Elemental Barrage 1.5x per shot. I took an Eldrich Archer Magus + Preservationist Alchemist through Unfair Chapter 1 and 2 with otherwise default companions and good success even at that stage, before Barrage comes on line it is a powerful combo. Here they are downing Vescavor Queen on Unfair
Another 20 levels in the same class powerhouse is Mutation Warrior 20 on Demon Path, since due to certain demon powers you can become immune to a large number of weapons in the game and have unbypassable 50% concealment. Go with an 18-20 crit 2-handed weapon (Falchion requires no feat investment, Else Fauchard or Elven Curved Blade) and go Enlarge Person almost exclusivly - Powerful from the start as Fighter 20 always is and by end game she was solo-auto-attacking almost every encounter. Demon gives a baby Magus spell book so you get the majority of Self-buffs through that and Demonic Charge makes up for your lack of Armor Training or Effortless Armor access which otherwise makes you a slowpoke.
Fey Sorcerer 20 has everything that makes it situation-ally superpowered in Kingmaker, but throw in 2nd bloodline and you can take Arcane as well. Its a wow from me. Likewise Phantasmal Mage can cast Weird with Persistent Metamagic attached, so you get to be Nenio+
Also re-creating Camellia is 10/10, I love that Shaman Archetype, Camellia not so much.
