I still view Charlotte to be worse than Alicia. At least Alicia openly dislikes Slow, whereas Charlotte is seemingly all friendly, but in reality she has zero faith in Slow, and is subtly letting him hear about it every now and then, while maintaining a smiling face. It's even worse Slow actually loves her.
@comeonnow0 It's probably more difficult to change your opinion on someone if you know a whole lot about them, especially what they are going to do in the future. You suggest Slow would find it easier, but I claim it's the opposite. Slow must have felt like there was no need to reevaluate the dude because he already knew what the man was all about.
Don't forget that living with a knowledge of a dangerous future is not easier, it's more stressful. It's easy to watch an action anime, knowing the MC will survive and win, but it's a lot harder to live through it, with no fancy deus ex machina saving you automatically because you supposedly must survive till the end of the last episode. Especially since Slow is actually changing the plot.