So here is my input on this.
First of all we're mixing a few things that I want to get out of the way. The screen resolution does not matter. At all. (Talking about art style ofc).
I understand that setting a virtual resolution for sprite development is helpful to see how things stack up. However, the discussion we should have is picking a reference unit to work with. We are talking about doing sprite art, so an easy way to do this could be to try to get a pixel to height ratio.
I'm not on my pc right now (neiter at home) so I can't give real examples of some things I would want so until I can give more insight on this, I suggest just using a ratio based on the double of the size of golden sun. So, basically, double the pixel density.
I don't have a preferred size in mind, but
sylvanelite approach seems the best one, which states 24x24, 48x48, 96x96 sizes on rolina example. So, to make a character for our game we would take a look to a golden sun character, and fit 1.5x more pixels on that canvas to fill out. This means that while scaling an actual golden sun sprite would feel strange (not 1:1 ratio scaling), making an entirely new one on that size won't be a problem.
I like this approach for the simple reason that we lack horsepower on the art team. And that is just the realistic approach. Also, in my mind resolution != quality. Sylvan's example of Hyper Light Drifter is a nice example on that.
Also, taking a 2x approach on golden sun pixel density from my point of view distorts a bit the original look and feel. If we take a high resolution to make a similar character we'll end up with a lot of "blank spacing" on, for example, the characters that while mantaining the GS artstyle (chibi characters) will feel a bit off because of having that much of pixel density to be fillment. To solve that we could add detail to the character (texture? Accessories on clothing?) but that would feel oversaturated comparing to golden sun sprite simplicity. Other thing that could be done is just to de-chibi-fy the characters. And that's just killing the look and feel.
Then, about screen sizes. we should target height ratios. Why? It's an industry standard. While most of the screens are 16:9, any game you run on 21:9 like 2560x1080 will just be the same with a bit of camera frustum space added to the sides. Being on a 2D environment, managing this changes on cameras is trivial and we could just target 16:9 (every console of this gen + 9X% PCs) and expand horizonally for ultrawides.
As 1.5x GS on the sprite density is loselessly scalable (pixel perfect w/o bilinear) I think this solution, while compromising a bit on actual detail density gives us:
1 - No headache on screen compatibility at all
2 - Lets us base sprites on the actual golden sun ones, just with ballpark of 1.5x sprites to add a touch here and there.
3 - Makes the art team easy to join and contribute to.
4 - Makes future 3D rendering conversion to sprites easy on 3D modelers. Making a sprite that fills 4x pixel density on a 3D model is HARD. 2X is not bad but 1.5x is (I think ; as I lack examples) just the same 3D model maybe with sprinkling some accessories.
Anyway, when deciding the sprite resolution I think the previous 4 points are the ones to take in mind. I personally prefer to have a super low-res style if that means artists won't have much more work to do to get out work. I think in the current state of things deciding based on our current work capabilities is the most sensible thing to do.
PS: Stealing GS sprites and 1.5x scaling them won't feel out of place, ofc for prototyping purposes :D
