"Conditions belong on one line" is completely opinion based and it all depends on the scripters style.
I, for one, find it more efficient to style as I do simply because it's easy to go back and edit things or add on things if needed. If you put the condition bracket on the same line then you fall in risk of losing your bracket positioning and possibly missing brackets or having too many.
Plus, this way looks a lot more clean IMO.
As for the character check for the NPCs, it doesn't really matter, since if it's not a character it'll set you to the default noob body, which isn't exactly a problem or anything. It's a fast way to get the noob body on for people that want it, though
Also, I try to separate condition statements for a reason. I don't really care about line length, moreso I care about flexibility. By separating your condition statements, it makes it easy to add else checks later on if you need to, without having to separate it at a later date and re-align the entire script just because you wanted to save a few lines in the beginning. It's not really lengthy at all with the way I style since everything is clearly presented. It's just easier to manage if you need to go back to it later on and fix or add-on anything.