Yo, yo, my dear spreader of colour and joy! Incoming YouTube stuff!

https://youtube.com/c/emmy
Emmymade mainly does food tasting and explores new, strange, and popular recipes, but she always does it with a smile and a laugh and she'll tell you about the background of what she's doing. Every so often she'll do a craft video, but most of those are back a ways in her upload list.

Jayda In Stitches is just so incredibly bubbly it's contagious. She goes through awesome crochet patterns as how-to's, and there's a lot of artistic yet practical pieces in her assortment.

https://youtube.com/c/JaydaInStitches

Although she has a distinct political inclination, Abigail at Philosophy Tube has the brilliant goal of giving people the knowledge behind a philosophy degree for free, and her videos cover philosophy in relation to current events with awesome and often amusing (and sometimes harrowing) presentations. Some of her stuff touches on sensitive subject matter, but i always feel more enlightened after watching.

https://youtube.com/c/thephilosophytube

Max Miller loves history and food, and presents historical recipes alongside thoroughly researched and beautifully presented historical essays about the food and the cultures it comes from. If you want to try some Roman Globi to celebrate Saturnalia or ring in the Lunar New Year with Nian Gao, Tasting History is the way to go.

https://youtube.com/c/TastingHistory

Beryl Shereshewsky loves foods from all over the planet, and she will cook and eat nearly anything for the sake of the experience and being able to share in other cultures' traditions. She also gets this 'look' when something is truly tasty that's always a joy to see.

https://youtube.com/c/BerylShereshewsky

I don't know if this counts as ASMR, but Dancing Bacons' largely dialog-free videos are an interesting look into food and consumer culture in Singapore and nearby areas of Asia. Videos range from self heating noodle bowls at the beach to robotic vending machines at the mall to street market snack foods, all with kindly captions.

https://youtube.com/c/DancingBacons

Chandi at Expression Fiber Arts taught me how to knit. Like, her video was the first one to actually make it CLICK for me because she took the time to show it carefully and supportively. Right now her instructional videos are mainly geared towards swatches of patterns from her website (some are free!), they're all presented in a beautiful learning environment, and the techniques taught can be extrapolated for other knitting applications. Stick around, each video concludes with a joyful blooper reel!

https://youtube.com/c/ExpressionFiberArts

Now, i know you mentioned wanting to expand beyond sewing, but you can't have a list of creative and supportive youtubers without mentioning Cathy Hay. In addition to her sewing projects, such as a beautifully ambitious replica of Lady Curzon's Peacock Dress, Cathy has beautiful gems of inspiring video essays that ring true no matter what kind of creative pursuit you're involved in. Cathy is that cup of tea that will help you ground and center and get through a difficult day with grace and inspiration.

https://youtube.com/c/CathyHay

This next one is cool, she's an artist who paints really cool, mainly abstract art. She sometimes shares things about her materials and studio setup and she's really, really inspiring. For some reason, she attracts spiders though. She's probably magical.

https://youtube.com/channel/UCz33Ix3V_ZE4y7XSA_X-bVw

And now a blast from the past with a generous grating of nutmeg. Townsends is a channel made of love for 18th century American history, and you can tell that Townsend really adores what he does. His videos are fun and wholesome, focused on historical recipes and eighteenth century crafts and lifestyle.

https://youtube.com/user/jastownsendandson

One of your other suggestions involved synthesizers, and if you like unique electronic music, you've gotta check out Hainbach. He makes music using old electronic text equipment and although his sound and process is extremely niche, it's also beautiful, both aesthetically and as a lesson that even mundane things can be used beyond their original purpose to create beauty and art. And his voice is super soothing.

https://youtube.com/c/Hainbach

Karolina Zebrowska is a Polish clothing designer and retro-dresser with an irreverent sense of humor. Most of her content is great for a chuckle - i recommend the lament of the time travel bureau seamstress - but some of her historical retrospectives are quite poignant. She also has a demonic iron.
https://youtube.com/c/Karolina%C5%BBebrowskax