Doesn't policing yourself on so many things take the fun out of the game?
Not at all. I don't see it as policing but rather attempting to make it more challenging. As well if I ever found the need to go on a barrellmancy tear or shovefest it's always there for me.
I don't have NPCs do things I don't think they'd do, like having Lae'zel give away her armor.
I agree with this, sometimes in a situation that is less clear I'll resolve it with a 1d10 just for further unpredictability. I rarely for example access Shadowheart's "guidance" (unless she is performing the task or interaction herself) saving it for occasions where she would potentially have strong motivation to use it.
