I was soooo excited to see Abi-Dalzim's Horrid Wilting, as it was one of my favorites in past editions. Then I read it and almost cried upon seeing how much it sucks. Fireball laughs at this spell. Sunburst, which is also 8th level, deals the same damage but also blinds creatures and affects an area that is several times larger. Sunburst also works on undead and constructs (horrid wilting doesn't), and very few things are resistant to radiant damage, unlike necrotic. Even circle of death is better than horrid wilting, and I don't consider that to be a very good spell...
Snilloc's Snowball Swarm is strictly inferior to shatter. It has half the radius, deals less damage, and cold is much more commonly resisted than thunder. Yikes. Ice knife, when cast at 2nd level, deals the same damage as snowball swarm to the same area, but also gets to inflict extra damage to the creature in the center. Just take that instead.
The good thing is, those are the only two spells that outright suck, at least that I noticed on my first read through. Most of the rest look pretty good. I love the new cantrips, especially control flames, gust, mold earth and shape water. Those look like a lot of fun.