Yeah, I'm having trouble getting the DIYs I'm missing too. My villagers keep cooking instead of crafting even though I already have all of the cooking recipes. Though I found out at some point that only particular personalities could give me some of my missing DIYs and then struggled to get a Peppy and a Sisterly for my island.
As for Celeste, someone told me that I could check if she was going to be on my island that day by looking inside The Roost between 5 PM and 7 PM. If it's already after 7 PM, then she shows up if you do a group stretch. That saves me a lot of time in searching my entire island every night.
I run a giveaway thread
here for my extra recipes in case you want to keep an eye on it for any new recipes you need. I currently have and will reserve for you:
Decayed tree
Tension-pole rack
Can I please have the stacked senmaizuke barrels? I think that might be the only duplicate on your list that I'm missing.