I'm into the less extreme Avante Garde music, so would someone recommend something similar to Diablo Swing Orchestra? They are the only band I have heard that mixes so many different musical styles and ends up with something amazing beyond words.

Mr. Bungle, Sleepy Time Gorilla Museum, The Residents, Idiot Flesh, and Naked City (extreme to an extent but they do genre blending the best imo) are all good places to start.

I'm not a fan of Pinkly Smooth, but they fit into the category as well.

These are fairly nice, if not a little hard to get into, but it wouldn't be Avante Garde if you liked everything about it the moment you first heard it! By less extreme I really meant stuff that still sounds like music, or at least similar to the established genres. I really like what I've heard of Idiot Flesh and Naked City so far. I like the fact that everything you listed is really energetic and upbeat!

The intro is pretty ****ed up, but the rest is really accessible. And energetic and upbeat.

If you're looking for some left-of-field genre fusion music, I think Koenjihyakkei could fit that bill.

I like those alot, the vocals aren't always amazing, but I like their instruments and style. Overall they're pretty great!

Koenjihyakkei are MASSIVELY influenced by Magma, so if you like that, check out Magma.

So I heard this is the place for recommendations :)

I was wondering whether someone could give me some avant-garde bands to listen to. A few of my favorite bands to sketch my taste: Kraftwerk, Goat, Swans, Sonic Youth, White Suns, Portishead, SQÜRL, The Jesus Lizard, Sleep Party People, DNA, etc.

You like some good stuff mate. Here are a few that might tickle your fancy: Melt Banana, Glenn Branca, The Thing, Renaldo & the Loaf, The Residents, and Fushtsusha.

I'm familiar with Melt Banana and Branca and I can't say I dislike them. Renaldo & The Loaf sounds interesting so far: rather goofy, but without degrading their music by an excessive use of gimmicky factors, as is often the case with such atmospheres.