Gaming

I am a huge Pathfinder fan (check my home instance) and have played both games.

Tl;dr, play Wrath. The plots of both games are standalone.

I hated Kingmaker. Incredibly frustrating experience. The game is difficult, buggy, the writing is beautiful in places and baffling in others, and the kingdom management is balanced poorly. It's easy to get yourself into a death spiral on kingdom management that takes 50 hours to play out (which then gives you an instant game over).

However, Wrath of the Righteous is one of my favorite CRPGs. I have roughly 200 hours in it. The writing for companions is much better in this one and while the army management side game still isn't good, it is a lot less frustrating and opaque than the kingdom management mini game. There are still some bugs... I had one game-breaking bug where I had to install a mod to teleport out of an inaccessible area after the game deleted an elevator. My only other complaint is that the ending was clearly rushed, but the campaign is about 100 hours and most of it is of excellent quality. Overall it's very worth it. The different mythic paths have tons of interactivity in the world, so it really changes each playthrough when you make different choices.

Also kudos to Wrath for well written evil companions and choices! You can be a psychopath that kills everyone you come across if you want (and there's even a mythic path tailored exactly to that), but there are also more subtle choices that allow you to twist the crisis at the Worldwound to your advantage (try Lich!). It is still satisfying to be a big damn hero, too.

I've finished Kingmaker and WotR is in my backlog.

Pathfinder is a really decent RPG system with tons of choice, but the game Kingmaker comes out as quite linear, you don't really have much choice in how you play the game apart from being good or evil.

The game is split between being a typical adventure explorer RPG and being a kingdom management game, the former is interesting and has good quests, the latter is opaque, difficult to get to grips with and inflexible.

The worse part is no matter your best intentions, it you don't do exactly the right things with your kingdom you can find yourself in a dire losing position by the late game.

I don't mind games that have failure conditions, but losing the Kingmaker game after 30+hrs of playtime because your kingdom starts rioting and you can't complete any events seems too harsh to me.

Personally I had to turnoff all the failure conditions in the options so that I could grind through the game to get through the final quests, it ended up leaving a bitter taste for the game which started off as promising.

I hear most of these issues have been addressed in WotR though so I'm looking forward to picking up that.

You can start with either, does not matter. I finished both, liked both. And both of the games were equally laggy and buggy for me. I sure hope the Rougue trader game will be less buggy.

I'd say start with Wrath and don't bother with Kingmaker. Wrath is just much more interesting both as a game and as a concept, and there's no shortage of replayability there - the amount of variability between paths is crazy. That said, whichever game you start with, I'd strongly recommend you download a mod to trivialise the management minigame (kingdom management for Kingmaker, crusade management for Wrath). They're a) not fun, b) difficult (and unlike the rest of the game have no difficulty settings), c) have nothing to do with the core RPG gameplay, and d) can brick your campaign if you screw them up.

Also, you know about Baldur's Gate 3, right? It's coming out in two weeks after a very long and successful early access period and it very much looks like all the crazy reactivity of Wrath on a full AA budget.