Story: 9/10

Saihate no Paladin starts off pretty "slow" by showing the protagonist Will growing up being raised by his.... unusual 3 "parents", but it somehow it's not as boring as it sounds, since it sprinkles some mysteries and tasteful worldbuilding, just enough to leave you curious. Telling more would be spoilers but it's enough to say that the story is pretty consistent and interesting as it's never too predictable or contrived and I'd say is pretty well-paced.
The only faults I can find with the plot is the whole isekai thing since it doesn't impact the story at all so far, it could've just been a fantasy manga and the story is not that unique by itself.

Art: 8/10

The art is fine, i guess ? It's definetly the low-point of this otherwise amazing manga, the art is pretty, but nothing special, not much to say there

Characters: 10/10
Will is a very rare case of a OP protagonist that's well-written and helps the story. Since the start of the manga is him being raised as a baby up until adulthood by 3 undead in an abandoned city while being trained by them (a warrior, a mage and a priestess) and specially when you learn about the past of these undead, it makes perfect sense that Will is really OP.
But since he was raised in an abandoned city with nothing but loving parents and training, he is naive about the outside world (not dumb) and makes his friendship with Meneldor (his ill-tempered elf sidekick) all the more enjoyable, the rest of the cast tends to be all great, but Will and Meneldor really "steal the show" at least so far.

Enjoyment: 10/10

I think I can't even really compare it to anything I've read before, it doesn't seem to have that special of a story, but at the same time, it tells it in a refreshing way and through great characters. It FEELS different to anything else in a way that very few manga can do, specially while "conforming" to high-fantasy tropes

Overall: 10/10

I can't recommend this enough to anyone that enjoys fantasy. It has a bit of everything you can wish for:
Good characters and character development;
Great worldbuilding that includes religions, geography, history and politics without ever feeling like boring exposition;
Emotional storybeats with really impactful themes;