You can't adopt Argonian kids, who would wanna have them as a pet/children
Hearthfire was and is pretty good. Its awesome because you can basically level up the 3 main skills that are needed to be overpowered. Alchemy with the greenhouse and alchemy table, enchanting and smithing. And once you get married and sleep in the house with your wife/partner you get Lovers Comfort which is better that being Well Rested so you could increase your skills much faster.
Dragonborn and Dawnguard are awesome dlcs. Solstheim is awesome, Dawnguard is cool because you sort of get to make a choice in what you wanna do.