I've been reading novels for years and I've finished reading loads of novels, yet I've never found a novel that has a protagonist who has lived for hundreds and thousands of years and acts like it, they all act either childish or not much better. A lot of them also still have stupid desires and longing, for example, I've read quite a few novels with the protagonist gets taken to another world and lives for dozens of centuries there all while longing for either another human or some stupid food they like, or living in a world of abnormal animals but no humans for millenniums yet still retaining their sense of humanity even though the years they lived with humans are nothing to the years they lived with solely monsters, it seems like no author has an actual sense for how long a millennium is. If there does by some chance exists a novel where the author has a clue of what a dozen centuries mean for a single human I'd appreciate someone pointing me to the right direction.
Check out Fantasy Simulator over at webnovel it's been good so far. From what I've read so far the mc acts like his mental age and is actually pretty smart in the decisions he makes. The only complaint I have is the word padding and the second time in the sorcerer world kinda drags towards the end.
I like RI's style but I got bored at the start and stopped reading, I'll try and skip over the start and see if I find any luck, thanks for the suggestion! I'll make sure to give it a try! I have read it and I like it though I don't think it fits this criteria. I've already read it! The protagonist in this one really doesn't act like he lived a millennium in relative solitude, I also don't like the angels and the stuff around the protagonist's family later on, but thanks for the suggestion.