yes, I'm the one responsible for the base switch. I'm not not sure it's as useful as I thought.
often, I suggest only one cIOS (base57 in slot249) to new people hacking their console to "go faster".
IOS base58 is never useful and I feel it started being suggested due to WiiU "contest to be the first to find a working setup" from random users who wanted fame.
having 2 IOS was always the norm before that but is not always needed, but can be useful.
most users want Call of duty, or games which require base57.
I knew only Spyro which needed base56, and needing additional NFC accessories I felt less users were playing that game so it was more right to suggest 57 by default.
as I knew only these games needed 57 and all others games worked fine with both 56 and 57, I thought it would be better to put 57 directly in the default slot used by loaders to prevent users creating an account here asking how to fix 2-3 games.
We usually helped them by saying to change their slot to 250. (or maybe more guide should explain that they should try to edit their slot in loader's setting in case of issues?)
I only recently (last month?) found that there are more games than I thought that require base56. Mostly Rock band, Guitar hero and we sing.
I started a wiki compat list here :
https://wiki.gbatemp.net/wiki/Wii_cIOS_base_Compatibility_List#IOS_Slots
I think most users only need one.
but there are always people who will want GH/RB, or all possible game with a full hacked setup.
for example, animal crossing keyboard support requires a base38 which no guide suggest, but it's only one game. I think it's best to not install unnecessary things if not really needed.
I also think it could be why VC N64 have better compatibility with rev17 : it used IOS38, while d2x only suggest 56/57/58.
I didn't test that theory, it's only an idea.
I would remove base 58, but again maybe there are lot of game which require it that I don't know?
At least, I'm very glad no more guide mix r52 and r53 with unique base each. (it didn't make sense for users who wanted port1 ending with one forced base, not always compatible with the game, like r53 base56 not working with CoD)
tldr:
you can keep slot249 with base56, as it seems more game need it than I thought. I really don't have statistics between Cod/just dance and spyro/GH/RB
both 56/57 and 57/56 are fine. no need to change the guides.
in both cases, it'll require a loader setting change to make all game working and both base are needed. I think it's more useful to educate the users to try different slots in their loader in case of compatibility issue.
no idea if it's good to replace 58 with 38? just an idea.
base 58 is sometime useful to initialize problematic HDD, but then the game won't work with said HDD as base58 has very low compatibility with games.
