For the most complete solution for all types of photo editing there is nothing better than Photoshop. It’s the grand daddy and it is the most complete and optimal.
If you mean "all types of IMAGE editing" I'd say Photoshop is a good all-rounder. But hardly perfect. For photo editing it probably is at first place in the league.
It really depends on the image editing job at hand, though. For example, Photoshop is TERRIBLE at 1bit image editing: no layer support, and most options are unavailable. Compared, PhotoLine offers best-in-class 1bit image editing, with full layer support. (I am aware this is an extremely specific task but one I have to do for comic work ;-) )
For pixel art editing Photoshop is "okay". Ideally a pixel artist works in index mode, but again: Photoshop's index mode is TERRIBLE: layers are not supported, many options again unavailable. Nor does it feature a specialized tool set for pixel art.
For the pixel artist either ProMotion NG or Aseprite would be at the top of the list instead, which work with indexed modes and offer full layer support while doing so. I prefer ProMotion NG, and detest doing pixel art in Photoshop.
And as you state, while Photoshop is great for digital painting jobs, again better options exist: ClipStudio Paint, Krita, ArtRage, etc.
Photoshop is indeed the grand daddy of image editors, which becomes quite obvious in various areas:
- The awkward way vector tools are integrated/patched in.
- Smart Objects are unwieldy and an unnecessary work-around for various non-destructive image editing tasks that are often implemented better in either PhotoLine or Affinity Photo or even Krita.
For example, in PhotoLine a layer can be any bit depth, any resolution, any colour profile, any image mode. Transformations are non-destructive by default. No need for inconvenient smart objects (even though those are possible to add too when it actually makes sense to do so!)
- The arbitrary 1 bitmap & 1 vector mask per layer. No such limitations in other image editors like PhotoLine or Affinity Photo.
- The layer stack is limited in other ways as well. Compare to Affinity or PhotoLine. Or Krita.
Want to apply an adjustment layer to another adjustment layer's mask? Sorry, no go! Only works destructively. Or work with inconvenient clipping masks. Which have their own limitations.
And why is the layer opacity slider range limited to 0-100%? Why not allow for negative values and higher values such as +200% and -200% ? This really opens up a flexible layer-based workflow. Granted, only PhotoLine is capable of this - but once I discovered that option, I really started questioning why other image editors stick to those arbitrary limitations.
- The inability to instantiate layer masks or other layers. With PhotoLine or Krita it is easy to create clones of any type of layer, and re-use those clones. Update the original, and the changes cascade throughout. Smart objects can sort-of be used as a workaround, but not always. It is impossible to reference an existing layer mask and use that layer mask in other places in the layer stack.
- The so-called "16 bit mode" is actually a 15bit +1bit mode. And Photoshop doesn't tell you that it removes half your data when you open a full range 16bit mode image in it!
- Photoshop's resampling algorithms are outdated as well. No CatmullRom for downscaling images, for example.
- The user interface is in places very outdated or inflexible. A simple example is the Curves window, which cannot be enlarged enough and is finicky to work with.
While I work with Photoshop at my job, every day I encounter various little and bigger workflow issues that are caused by legacy development decisions that were never updated since they were first implemented - and some of those stem from the nineties, such as Photoshop's "16 bit" mode.
For example, I cannot use Photoshop to create 16bit texture maps for displacement. ANY other image editor with a 16bit mode can handle it. Just not Photoshop, because of its outdated code. And that is frustrating.
Of course, no image editor is perfect. I run into limitations with PhotoLine and Affinity as well. That said, Photoshop's legacy core code is somewhat problematic. And the layer stack should have been improved ages ago. So much potential there, yet it's still the old antiquated layer stack from almost 20 years ago.
