I absolutely love this game, but it a lot more fun with at least one other person of similar time investment.
+you can play through 90% of content solo or with one other player. You can increase the difficulty (and rewards) with additional people.
+instances mean no kill stealing or reward hogging, so much better than open-world click-fests.
+omg, the character building. there's so much fun to be had putting together a character of 10+ races and 12 classes, and you can mix up to 3 classes on each character. Self-healing combat wizard with trapping ability? Sure.
+traps and secret doors abound. you'll miss a bit of this if you zerg through (see below), but it's a lot of fun to work through for the first few times per instance.
+while content has been recycled rather than created, the character options are coninuing to grow, especially for melees.
+you get an incredible amount of game for $9.99 a month.
-it's so old and desperate for players that easy mode is a lot of places: guild buffs, hirelings, and some pay-to-win options.
-power creep was inevitable, but it can be pretty absurd at times comparing similarly-leveled characters of newer plyers and vets; as a result, most content is sped through at its highest difficulty in pugs, and it can be difficult for newer players to contribute or even keep up.