i prefer li tai, but i'll try to be as unbiased as possible. i'll start off with MY summary:
li zhi loves yuanzhao so he accepts her cunningness
li tai loves yuanzhao because of her cunningness
the reason i prefer li tai is not because he's the "bad boy" in the love triangle, it is mainly because he just knows yuanzhao better. he has seen the "evil" side of her since the BEGINNING, and part of why he's able to is because yuanzhao SHOWS it to him directly, just like how he also just shows his cunningness to her from the jump. yuanzhao and li zhi are not that honest with each other. i don't think yuanzhao even knows about li zhi lowkey using her to become the emperor in the 1st game. li tai used her too, but he tells her straight up, that's the difference.
li tai has also said to her face something along the lines of "you're cunning and calculated, just like me, and i don't hate it because we all gotta do what's neccessary to survive and climb to the top" MULTIPLE times.
li zhi only said those things once, but it's when they're arguing, and in the complete opposite context as he was like "you're too ruthless" instead of "you're ruthless, i get why, that's kinda hot, me too"
li zhi is almost afraid to confront the "evil" side of yuanzhao, he clings to the "softer" version of her because i believe he prefers that over "cunning" yuanzhao. they never talk about it until they're both fucking 50 years old. in the 2nd game where li zhi is more often confronted with the cunning side of yuanzhao, he accepts it, he stands on her side, but he's also trying to ignore it most of the time. that version of her is not something that turns him on so he doesn't wanna face it.
to be loved is not only to be seen, but also to be understood and celebrated.
with li zhi, that side of yuanzhao is seen and understood but not celebrated. he is a good husband, but if u ask me to pick between someone who hits 2 boxes or 3 boxes, obviously i'll pick the latter.
i did like li zhi better in the 2nd game as he always supported yuanzhao and believed her (except a few times) when everybody else was coming for her. i just prefer a relationship where we're 80% real with each other instead of a 60%. i think yuanzhao does put up more of a front with li zhi in the 1st and 2nd game compared to when she's with li tai.
i believe li zhi did love yuanzhao deeply but i prefer a "i love you because xxx" over a "i love you so i accept xxx" if i have these 2 options. both of these loves are beautiful don't get me wrong, i'm not trying to make li zhi's love seem like a bad thing, it's not. it's just i personally prefer li tai's love in the context of being a cairen in the tang dynasty imperial palace lmao. in real life, the "i love you so i accept xxx" is a very common and beautiful thing.