After looking through what Switch game icons cause a lot of outcry because Switch users seem to be incredibly particular about those things, I’ve narrowed down the general guidelines that seem to pop out when looking at what’s common between “good” icons and “bad” ones, as well as how icons have changed over time, aside from the ones where they’re changed to promote some update. There might be more subtle things I’ve overlooked, but these just stand out pretty clearly after giving things a good look.
The big one seems to be that treating a Switch icon like a phone app icon is a major thing to avoid. Maybe it just looks incredibly generic, or possibly insulting to Switch users by considering their device a phone, and therefore on par with all the bootleg crapware that gets shoveled onto the Google Play Store and on occasional the iOS equivalent. And there are a fair number of phone game ports that show up on the Switch, for better or worse, depending on how good the games actually are.
What a “phone app icon” seems to constitute is possibly a close-up of a face, or just a minimalist logo approach. This seemed to be fine from the DSi through the Wii U, because they’re kept small on those devices, but Switch icons take up a fair bit of the screen, and this is a device that not only has its own portable screen, but can dock and use a giant TV if one’s attached to it. Therefore, the icon design has to also fit a “ten foot” (TV) design as well as a “one foot” (portable), terms referring to the possible average distance of a device from the face. Minimalist logos can work in these contexts, but they have to be carefully considered. Having a lot of tiny text is probably not a good idea as well, but it could have some readable text. That text should probably not just be a corner with a year, sequel number, or even the developer or publisher logo pasted on, either. Rather, it should probably be the title, which leads into the next point.
This next point I’ve found is that the icon should be treated like proper box art, complete with a title. The title thing seems very important on the Switch, as in its larger library grid view, there are no titles shown alongside the icons, unlike other consoles, or even phones which may have even a tiny one or two-word descriptor under the icon. This also applies to the one-row main screen view, where the icons are shown large on the screen. I’ve noticed on the PS4, though, that this similar thing exists in the main menu view, where all you can see are icons, with only the title shown for the currently highlighted one. However, I’ve heard less about PS4 icons not fitting to some code, but I could use these Switch rules to pick out ones that wouldn’t fly on the Switch.
The last major point I’ve found is that the icon should generally have good art overall. It ties back into the proper box art argument, but the art needs to fit in whatever way is intended, and probably not disagree with the general public’s aesthetic opinion. In short, it shouldn’t be “ugly”. An icon can get the first two points right, with proper composition and title present, but maybe the art is just… not appealing. Maybe it’s a badly composited or scaled screenshot of a pixel game with blurring artifacts, or the art style in general feels very unintentionally off-model. Apparently borders are also a no-go because the Switch already handles icon separation. For all I know, that could also apply to mobile app icon design.
If there’s other aspects I seem to personally disagree with, it may be along the lines of retro re-releases using a screenshot of the game, but just throwing borders around it with the name of the game and some “collection” it might be part of, like whatever arcade collections are being uploaded in pieces nowadays. I don’t know why they can’t use something like the box art, cabinet art, or the game’s actual logo instead of something really last-minute-looking. As well, it also makes it feel like someone could be getting ripped off by buying these games individually, like there’s some actual complete collection that’s either in the works or would have come out alongside these individual games. That’s my personal annoyance with some of these icons, and I’m not sure how far that sentiment is shared among the general Switch icon enthusiast crowd. Now I’m just wondering which PS4 library icons could work as acceptable Switch icons. I can already think of some with issues in that category.