Honestly liu bei can be a bit much with all the virtue talk in the games but there are some good ways to make him more interesting. I feel like the first thing they could do is tone down how often he brings up benevolence - let him show it through his actions instead of constantly preaching about it. Maybe have him actually helping villagers or showing mercy to enemies in cutscenes, that kind of thing.

Its pretty cool when games give characters some moral challenges too, so throwing liu bei into situations where being "good" actually costs him something would add some nice depth. Like imagine him having to choose between helping refugees or keeping vital supplies for his army, that sort of thing really makes you think.

I always thought they could do more with his relationships too, like with guan yu and zhang fei. Show us more of that loyalty and brotherhood stuff instead of just the virtue speeches. And hey, why not let other characters call him out sometimes when his idealism gets a bit much? Even zhuge liang could point out when hes being impractical, which would make him feel more real.

The contrast with other leaders like cao cao is really interesting too when you think about it. Having liu bei struggle a bit with staying benevolent while dealing with more pragmatic rulers would definitely make his character more engaging, rather than just being mr nice guy all the time. Just my thoughts on making him a bit more three-dimensional without losing what makes him unique.