I'm really glad you can co-op the new Childe fight for the weekly rewards, it's actually kinda fun doing co-op there. I'm making good progress on strengthening my characters, just unbound a ton of weapons today running the 2 weapon ascension domains. Childe is such a fun character to play, and it got way better after his level 70 ascension. Now I can actually apply riptide without using aimed shots, and his AoE damage is crazy good in tight groups. Can't wait until we get the full hydro damage bonus artifact sets next patch. I'm also getting pretty good at swapping Beidou in for counters too, it's a really satisfying way to play. She's still a good 30 levels behind the things I'm fighting though, so if her shield gets broken she pretty much gets shit on, even if she perfect counters. Had a pretty good laugh when I proc'd a counter and exploded a bunch of barrels, killing her in the process.
Also, found out that if you're building artifacts and don't want to level intermediate ones, you can get a lot of bang for your buck on the feather of whatever set you're using. I guess the flat attack is added in before the %s are calculated, so it's actually a pretty big overall attack boost to just level that one up ahead of the rest. That also made me look at ascending/leveling weapons a little differently, as it's a bit bigger of a priority than I was considering.
I'm going to hold off burning any more resin on xp leylines this week and spam that event, hope we get the same or better resin rates per xp book as the alchemy event. If so, I'll likely burn my moon resins and just stock up.