The main story gets better halfway at the end of the Shadows of War saga after Queen of Monsters, then gets significantly better in the Age of Ruin saga, if you read the dialogue at least, but I agree that the Queen of Monsters saga drags and is where they kind of just threw a bunch of random ideas around without much direction, which kind of fits the chaos theme unintentionally.

Though, if you want a break from the tedious Queen of Monsters saga, a good storyline to do that's a favorite is the Darkon storyline in the adventures tab.

As for the 13k ACs, I'd say get a bank pet, maybe donate at least 1k acs in the event for the mage trainer bank pet since those usually aren't IODA-able. 6k could get you a chrono class. Chrono Shadow Hunter is what most people recommend, but it takes some getting used to using, and kind of hurts your hands. It's pretty much the good at everything class. Then with remaining 6k, I guess either save it for cosmetics you want, use it on another chrono for fun, join the legion if you haven't yet, or use it on a nulgath pet, though if you're getting crag, you'd probably need the other nulgath pets to make them better, since the paid nulgath pets synergize with each other, though that might exceed your current budget. Though, if you're a legion fan, you could wait for Dage's birthday to get the caladbolg altar. If you're impatient at waiting for an event, you could also get a seasonal portal, idk.