That feels a lot like being billed as an IM alternative to me.
G'MIC is really good at that kind of thing. I wouldn't use it to replace ImageMagick though.
I don't know what your standard is when it comes to software but by this point I'd expect a lot more out of what we have. I've experienced nothing but headaches with imagemagick. Have you ever tried to use it for rasterising a pdf? Forget about it.
The only other alternatives I'm familiar with involve 3rd parties and web based apis. If you want to perform image editing in an app, it seems like its the only choice.
I don't think this software is an alternative to imagemagick, but those are my thoughts on imagemagick since you asked.
Plus it comes bundled in with Krita and Gimp.
Just as a sidenote, if you like playing around with G'Mic, you might absolutely love Python+OpenCV+Numpy combination. It's crazy powerful for tiny amounts of code required.
The IM/GM command line is also a disaster of weird names for things and inconsistent conventions and hundreds and hundreds of pages of manual. Reinvent IM's command line to be pleasant and simple and make sense, and it'll be a HUGE win!
What we really need is an open source alternative to is Nuke or Shake (RIP). Anyone want to help build that? ;)
I can't get to the project page, but I hope that GMIC borrows the positive developments from GraphicsMagick. One of the things GM improved over IM is large image handling. GM can stream a gigapixel image resize in minutes, while IM gets stuck in virtual memory swap for hours.
It's still quite young imho, but it's very promising.
Incidentally, it also integrates with GMIC
What makes filters more ugly to me is filters that aren't very functional as a building block or a node in the middle of an image processing graph. When I said aesthetically unpleasant, I was thinking about design too, not just the aesthetics. Filters that include any aesthetics at all, frankly, are not very useful, and that is the main problem with many of G'MICs (and ImageMagick's) filters. Photoshop has some too.
I'm using https://gmicol.greyc.fr/ as the reference for filter names.
G'MIC Filters that are useful as a building block (filters you're likely to find used by professionals), and are not aesthetically unpleasant:
Basics, Colors|Channel Processing, Contours|Difference of Gaussians, Degradations|Blur, Details|Sharpen, Repair|Upscale
A small sampling of G'MIC Filters that are aesthetically unpleasant to me, primarily because they are poor building blocks (less likely to be used in professional work), secondarily because they add an aesthetic that I personally don't like, and try to do too much:
Arrays|Puzzle, Artistic|Ellipsionism, Deformations|Rain drops, Frames|Tunnel, Lights & Shadows|Shadow Patch, Patterns|Hearts, Rendering|Cupid, Sequences|Lava Lamp
Note that many of these could be re-created easily using proper image processing building blocks, like an over operator for compositing, or an expression node for image warping.
A plug-in gmic_gimp, to bring G'MIC capabilities to the image retouching software GIMP.