Believe me, I totally respect your opinion...mine just differs on 2 points of your comment.

I would pay 20$ for the Companion's DLC. Comparing the two in your example, one must understand that the Companions DLC would have added Jorrvaskr (which wouldn't have been included in vanilla) all the related NPCs, Quests, and Items such as Wuuthrad as well as the Tomb of Talos. It would have also added the Werewolf feature (which wouldn't have been included in vanilla).

While I understand you point and respect that you wouldn't have paid 20$ for that...I most certainly would. Matter of fact, one of the major features of Skyrim for me was being able to experience the game as a Werewolf, so if it wasn't included in vanilla I would have gladly paid 20$ just for a small DLC that added that feature. For me, that's akin to adding another race. Would you pay 20$ for a DLC that only added the Dwemer as a playable race? Perhaps not, but I may.

I don't claim to be an expert (yet) on the scaling of either form. It's something I've honestly never paid much attention too. My reason? I've been having so much fun with it. Either form is just a viable at level 10 as it is at level 20, level 50, and now I'm level 71. At 71 on my Vampire Lord, I'm silent death. Its as good as a god mode cheat for me, and I play on the Xbox360. I change form and waste everything in my path. Its so much fun, and yet a bit unfair at times because most of the mobs just don't stand a chance. Same goes for my Werewolf. That character is only 63, but still, its ridiculous how fast I'm able to down a group of Thalmor casters or clear out a dungeon.

If you really feel that is useless to you, then that's very fine. For me however, it's quite the opposite.

for me it isn't about how many hours it added, it's about how it made my game more interesting just as I was getting bored so I've squeezed loads of hours out of it. Definitely worth the price in my opinion.

I am in the process of playing through both sides. The Dawnguard side lasted 40ish hours and as of right now the vampire side is about 15 hours and I maybe halfway through the vampire side so you can add at least another 10 hours for me to complete the vampire side. 40+25=65 hours, if you think 65 hours of game play isn't worth $20 then your expectations are set a little high.

Logic = DLC that has more content than many games released right now for less than half the price is good.