If I may say so - while Sinestro does several "cool" bad things - he just looks lame as a great super-villain. I think it's not just the moustache but that he has them "waxed" so that they are standing out as straight lines and pointed or whatever. How can you take somebody whose moustaches are waxed/pointy that seriously?
I noticed the "Fear" thing actually starting out with the Red Lanterns where there would be several captions in a red background with the word "RAGE." in them. Before that, I don't seem to recall a "Fear" caption being used much.
Also re Sinestro being afraid, it could be that he's "afraid" of chaos and that is why he believes in such rigorous dictatorial order (that pretty much had his entire planet Korugar be enslaved). However, having said that, I don't think the Yellow Ring Corps is a model of "order", at all. Quite the opposite. While Sinestro always has a plan and such and the Yellow Lanterns probably do fulfill those (including sacrificing their life in certain cases for him), I still think it's not a very organized corps. Also, while he uses the Yellow Lanterns, Sinestro has made noises that makes it seem as if his real goal is to be the leader of the Green corps and not the Yellow corps.