The disgrace to the fallout universe award goes to dead money... HH could have been better but it was good imo
Broken Steel was by far worse.
Be wary of the haters and their reviews. Many of them have very particular reasons for not liking the DLC (playstyle; views on what a DLC should be; anger at how certain individuals are presented) and those reasons might mean nothing to you.
Overall,
in my opinion:
Characters post-Happy Trails were boring and not very innovative. Daniel simply wasn't interesting, he's a nice guy trying to do a nice thing, those kinds of characters are just boring to me, and Graham was a walking cliché of good guy turned bad turned good with a tint of evil. Follows-Chalk was awesome though.
Difficulty lies with White Legs and Spore Carrier Brutes, the rest are cake walk, and this was with a gimped character.
Story was quite linear with some choices by the end, overall it do railroad you into helping the tribes although one can spin it by RP reasons.
Environment was beautiful and the rain and the night sky made it one of the greatest locations I've ever seen in a Fallout game, visually.
Quests were very repetitive, mostly fetch quests of "Go here, collect/place that.".
Exploration is very supportive to Survival characters but for others it's locations don't really hold that much interest with the exception of the Survivalist terminals. And about 80% of the locations did not need map markers, now the map is ugly as [censored] with map markers all over the area, should've only had markers for places that actually hold some interest.
The weapons in the DLC didn't really fill a niche and mostly just felt as filler weapons, new weapons for the sake of having new weapons yknow. I don't hate them or disapprove of new weapons, but it wouldn't have chipped the DLC if most of them weren't in it.
The new clothes and armor was much appreciated for RP reasons.
I don't hate the DLC, I like it, it just comes at 5th place of all Fallout DLC's to me.