I didn't a lot of early canceled manga before Manga Plus occured. However I really liked Stealth Symphoni, and Noah's Nota had an interesting plot imo. I had huge expectations for Beast Children but it really wasn't that good.
For Yozakura, I've been part of the one who ad been really hyped in the beginning by this manga, but like a lot of you right know I don't where it wants to go, and even if it's not bad it is not what I thought it could be.
Mitama is probably the biggest surprise to me. After the first chapter I was like "what did I juste read? how can this be published in WSJ?", it tooke at least few chapters, but right know I am really enjoying it, we are starting to have several spirits with their own characters and the lore is starting to get explored so I'm excited to see what ill happen next.
ZIPMAN is pretty cool in my opinion, nothing original that's for sure, but I like the art and the story isn't that bad so I'm stiking to it and hopefully it will good. The 3rd chapter fight wasn't really good, has I wasn't into it, but how the brothers interacts made it more appealing imo.
Last but no not least : Agravity Boys. Well, after the first chapter, I thought that it wasn't for me. But to be honest this second chapter made me rethink that, I even laughted. The thing that happen during that chapter made me thing that it could create funny situation and more that just the original plot woth the "who is going to be the girl", I think it could really develop something and we are in space so other non human characters could complete the cast. I am looking forward to it, even if I doubt it will stick arounf for a long time! Wait and See !