i really enjoy black gem foundry, as it is a bit of a challenge to solo through as a dps on normal due to all the dots the elites and bosses have
naj-caldeesh is kind of annoying with the pressure plates to lower the bridge right at the start, the side content is interesting but difficult to impossible with less than 4 players (the first side can be done with 2 players and practice, the 2nd side is very difficult with 2 players but is also possible, the 3rd side is downright impossible with 2 players even though it requires only 2 players to open the secret area)
i have my main house (grand topal hideaway) listed in the housing tours, it has multiple target dummies, scribing altar, and grandmaster stations (in progress being filled out), as well as almost every antiquity furnishing on display to preview them