Woah woah woah, making deals with devils doesn't make you an evil person. Plenty of people (in media/D&D campaigns) make such deals in order to achieve some decent, even Good, goal!
Now, is it also true that these people often succumb to the temptations of power and/or the influence of the devil, and end up becoming evil? Sure. But "road to hell is paved with good intentions" is a very different character & character arc than "should be evil, but is secretly good!" It's practically the opposite, if anything.
So I'll strongly disagree that Wyll fits that single character stereotype, but I'll also add in NPC
as a character that does fit. So we have SH, [redacted character], and possibly Helia as "should be evil but actually good" characters. Which is...on the edge, for me personally. If Helia isn't in the game or doesn't fit this character type, then we'll only have 2 notable characters which isn't a really a trend.
Astarion is just evil. Should be evil & is actually evil. Consistent!
