Tried abyss again last night with my newly powered up team and flew right by 3-3 and got my free Xiangling. It feels good to come back and just lay waste to 3-2 which was giving me so many problems originally. I think the biggest overall power boost you can do is picking good "main" stats on your artifacts and leveling them up. I can see that getting the "right" substats on artifacts is going to be the meta at endgame. Be aware that it's gonna be fuckin' expensive though, and you really need to level them up to 4/8/etc to see which new substats you're going to roll. I wish you could use enhancement crystals on artifacts instead of just weapons, but I haven't found a way to use them yet.
Now granted, I've been basically no-lifing this game the past few days, but I'm a little worried that the world is starting to feel empty after collecting all the shit. I can foresee a pretty big drop off once more people have collected most of the open world stuff. Resin regens way too slow to make running dungeons/leylines a substitute for exploring. I hope they have events planned out for the future that add interesting things to the overworld, hopefully repeatable and without needing resin.