I like to revisit mmos i've played in the distant past for a few weeks before moving on to a single player game binge.
Right now i'm revisiting Maplestory and BDO.
They're definitely different from their release state and there's been some improvements, but they're still pretty terrible since kmmos are inherently kind of bad because of rng progression those gooks seem to obsess over. They do have some neat ideas in there. Maplestory as more engaging bosses than before and BDO's combat still hold up and i still enjoy the pvp, but that might just be cope since i miss Tera's combat.
A couple of friends have been playing with the idea of going back into XIV and thats another i haven't played in a few years, but they've been toying with the idea for a year now and have just instead play League stating that life is busy. Maybe it's for the best, since i hear it's not really in a good state now.