I agree about the cosmetic DLC. People need to get a life instead of bitching about that. If $20 feels too expensive for you, don't buy it or buy a code later for cheap from a reseller or a holiday deal or something. It's not DLC that you need to play the game; it's just cosmetic shit. You're very safe to ignore it and your game experience will not be any different.
There is fair objection, however, to the pricing of TTK in the context of past expansion offering quality from season 1, the "walling off" effect DLC has created with regards to playing with friends, and the arguably thin amount of content expected to be included in this expansion. In the context of gaming, $40 is quite a bit of money and the quality and quantity of what's being added via expansion pack should reasonably well match the asking price. When it doesn't...or when price packaging is unreasonably obtuse...well, you get threads like this.