I dont play raids and fractals or pvp. Im doing dailies and landscape group events + story. I have some events that I really like so I often do them. For example Claw of Jormag. Sometimes im spending time in HoT, while sometimes on Central Tyria events, and sometimes mixing both. I like PoF as expansion but didnt find any extra event there that I would often aim to do.
I must say those events like Dragons Stand, Claw of Jormag, Tequatl, that big one in Auric Basin... are right up my alley.
What gives me more fun is doing achievements for something good. Like some gear or like atm Im doing skyscale achievement.
I dont feel like Im playing solo because I often interact with people through say/map chat or I join commander groups. Even when my character is downed and when some person from far away comes to help me is form of interaction that I find nice.
I like how you can in this game play with lot of people but you are not forced to do raids. I think this game have some of innovative design ideas when comes approach to group game. I know other MMOs have public events too but I think GW2 made best job with them.