Finding someones adoptive mother... you mean Minfilia asking you to find F'lhaminn? Or is this another mother figure im not remembering? Because youve found F'lhaminn before you finish the first 3 quests after Ultima Weapon. Yes, that is a lull in the story but 3 quests is tiring of it fairly quickly. As was mentioned, these are the patch-line(2.1-2.55) quests for ARR. There is relative peace. The threat of the empire is a distant one for now. The scions look to stabilize their position in the world, the alliance needs to decide if its still necessary and expand its position if it is, everyone is interested in opening up Ishgard, and the warrior of light has a few problems to deal with along the way(some minor, some major). By design this starts out slow(every X.1 patch is fairly slow - we just had a major climax in the story afterall). The story stays fairly low for the first third of the patchline(it sets up a lot of story, but the payoff isnt immediate or apparent right away). At about the 1/3 point, youre dealing with the sylphs again(a Ramuh sighting in the forest?). From there til the end things start to accelerate. Events become bigger, trouble more obvious, and Ishgard really starts to take the center stage. By the end theres a second climax that hits as hard(harder for some players) as the Ultima Weapon one, and then the gates of Ishgard open and you get to experience the Dragonsong War firsthand.
How long all this takes? Some players burn through the patchline in under a day, others lose hope and never finish(quitting before the end). Content wise, you are required to do 6 new trials, 3 re-fight trials, and 3 dungeons along the way(one of which is potentially a re-fight) - and as Iscah said we're hearing that the 3 alliance raids will also become required at some point(and this is the logical time to do them story-wise, though you could come back later). There are also a handful of overworld fights and some solo instances too. And of course, Iscah also mentioned that the next patch(this summer) is supposed to be trimming this section of the story a bit. Impossible to say what that means yet. My advice to new players is to focus on the MSQ for this section, and stop to do some of the optional stuff if you get bored and need a break(a bonus dungeon here and there, the alliance raids for story, the hildy quests to lighten the mood, etc). Glancing at the other thread, it sounds like you might have stopped to do a bunch of the optional stuff first. There is light at the end of the tunnel, and if you walk a little further youll get to bask in it.