Damn, this is practically spot-on with my own impressions of the game. I was also frustrated to no end by it despite finding some enjoyment in some of the stories and quest/character arcs. On the Obsidian forums someone asked how Kingmaker compares with Deadfire, and I wrote the following in response:
I wasn't a fan [of Kingmaker], and it's a massive time-sink, probably twice as long as Deadfire overall and largely because of a lot of trash encounters, artificial timers surrounding the kingdom management system, and a much more extensive main story opposite to optional sidequesting and the likes. However, I would recommend giving it a try at least. It has its worthwhile elements and others have loved it so, who knows? As to how it compares specifically with Deadfire, well... I think it doesn't. I started a second playthrough of Deadfire as soon as I was done with Kingmaker and the more I played, the more the problems in Kingmaker became extremely apparent. Kingmaker is a pulpy high fantasy power trip, your goal is essentially to rise from novice adventurer to king of an entire new nation, and amidst it all there's numerous threats to your realm and pretenders to your throne, plenty of big epic stakes and enemies, but it's all very surface-level, it's all there for spectacle and entertainment's sake. Nothing wrong with that of course, it knows what it is. But Deadfire, as most Obsidian games, thrives a lot more on a solid thematic foundation, and even at its pulpiest there's still a sense of purpose to much of the content therein, if only to describe another facet of this world that is so deeply tied with the undelying discourse the game presents.
And whereas the writing in Kingmaker frequently comes across as crude or generic, there's a life and character to the particular cadence of the Huana or the Valians that is unique, lively and very underrated when in contrast to the former. From a sidequest or side content perspective, there's no doubt in my mind that Deadfire's the better game - most of the side content in Kingmaker is lacking, the sidequests tend to be very straight-forward and not plentiful, whilst 80% of what is there to discover in the world map amounts to endlessly rehashed small areas that act as little more than "arenas" to trash encounters. And whilst the game does react to the choices you make, these are almost exclusively dialogue or build-based, and often dialogue options are gutted outright by arbitrary barriers like alignment - in comparison the roleplay in Deadfire seems much freer and more plentiful, as quests and area design allow for a player to resolve the same in multiple ways just by choosing to play the sequence differently instead of merely choosing a different dialogue branch. The freedom of exploration and liveliness of the world stand out a lot more in Deadfire when directly compared to Kingmaker, which on the other hand feels generic to a fault, if no doubt appealing on a sheer comfort-food level.
All this without touching the worst aspect, which to me is the combat. Kingmaker's combat is absolutely woeful, ubiquitous and inescapable. If the first Pillars had a trash encounter problem, this one has it three times over. And all this without taking into account that the game does everything in its power to worsen and exacerbate every flaw in the IE games' combat system as well. This is the kind of game that follows the same balancing principles as a regular combat/strategy mod for Baldur's Gate II in that even in normal difficulties it requires you to have the prescience of knowing what you'll face when and what scrolls and characters to bring alongside you for which area; and since the game is on a timer all throughout, backtreading to acquire X or Y supply or companion is very costly. This is essentially a game where prebuffing isn't just a clever and accidental workaround to combat the way it proved to be in the IE games, it becomes a mandatory element through which all encounters are balanced around - and if you happen to forget to prebuff your party for a single trash mob of spiders (which can also occur as a random encounter on the road), then good luck because you'll likely end with two or three characters sporting a massive -8 STR, DEX and CON permanent debuff at the end of it. If you think this is just a single type of creature, or just a couple who can do this, think again, because basically everything here is capable of dealing attribute damage or permanent afflictions (see blindness too) to your party - and that's not even touching on several other baffling enemy designs like the AoE paralize auras on the Wild Hunt which themselves become your usual dungeon filler during the end of the game.
Other irritating features, as with the IE games, include crowd control conditions and DoT AoE spells alla Wall of Blades, Web or Cloudkill enduring for minutes after combat ends, rest interrupts and random road encounters consisting of trash mobs are plentiful to the point you could well have four or five of the former and two or three of the latter occur before you finish either action, enemies having a tendency to be dumb and heavy on spamming single moves or attacks (case in point: alchemist enemies tend to bombard you with a seemingly endless and constant barrage of fireball, regardless of whether it's effective against your party or not (say that we've cast communal protection against fire on ourselves for example), despite also wielding a crossbow for example), and these shortcomings in AI tend to be 'balanced' through inflating base stats and abilities to absurd degrees, to the point that even a regular boar in act 1 can have an STR score of 32. It's compared to games like this that you realize just how much great work has gone into redesigning and improving combat in the Pillars series. All of which also leads me to the bottom line which is...
Kingmaker is very likely a game served best by playing with cheats and cheat mods on. Movespeed cheats, difficulty down to a bare minimum, even the removal of random road encounters, anything to not have to deal with the relentless, tedious combat in this game and nevertheless allowing you to experience the story and several companions and companion arcs which are all very decent - I'd likely have enjoyed the game way more had I played it this way and not tried foolhardily to beat the game at the difficulty I did. Anyhow, these are my thoughts on the matter, hope they're worth something.