This is the type of MC I most like playing!
My most “saintly” MC is in “A Mage Reborn”, a WIP. It’s a bit subtle there, as it’s mostly the MC’s decisions and stuff like that that make it. Still, there is a lot of small variations to flavor text depending on personality.
“The Ballad of Devil’s Creek” is a pretty peculiar one - the MC has a semi-set personality of being a bit snarky and stuff, but at the same time, you can really make an extremely nice and sweet character, even if the first impression the characters will get of them won’t necessarily be that. The game really acknowledges their personality though, even in the phrasing of some choices and stuff like that! That one’s also a WIP.
“The Bastard of Camelot” (check it out here), a WIP that’s moving to Twine really allows for a true saint of a character, but at this point in time the MC is a kid so the world around them still reacts more to the rumors surrounding them than to their true personality. Their personality WILL impact things more and more though.
To a degree, “The Exile” WIP is a bit like that too - the MC has some predetermined traits, but you can really shape your character like you want, including a very “knight in shining armor” type. The only thing I need to mention is that the game is really dark and sad, so everything will be a bit jaded.
Then, let’s not forget “Fields of Asphodel”, where the MC can be the sweetest most adorable thing ever. And yes, that’s also a WIP.
And yes, I know I did mention most of my favorite WIPs… But they are not my favorites without reason 
Keep in mind, there are a lot more, but these are some of my favorites!