The purple dimension
This, here, is the problem, you see. If the vampire lords were on a mission to spread rainbows across the continent, there would be no need for the Dawnguard. Instead there would be a Hugsguard, on hand to deliver a friendly welcome with military efficiency. But NO. Instead they're all "let's blot out the sun" and "let's change reality so what when buildings collapse they'll collapse UPWARDS because that will REALLY mess people up." Perhaps the decision as to whether to join the vampires or not really comes down to how much you like the colour purple. If so, back 'em 100% and look forward to lots of scenes like this.