Servers can monetize shit however they want, I am specifically talking about Rules for Modders, not Server Owners. And yes a Mod that allows Server Owners to customize monetization without resulting in the Modder getting a cut from said monetization (unless they literally host the Server themselves), would be allowed on the Forums.
As for the Keybinds Part, unlike Minecraft, the Keybinds are stored per profile, so using a different Modpack that has some Mods in common would still have the Keybinds stored for each Item.
And remember that the case of “prompting for keybinds” is also discouraged for the mostly useless bindings. There isa reason a generic “Action Menu” exists that contains all the things you can do to a Block or with an Item, so you can bind it yourself there if you need to use it often.
The only things people should ever get prompted to make a Binding for are Jetpacks and other Movement related Keys. “Mode Switch” Keys and “Open Custom Inventory” Keys are NOT supposed to ever have Defaults, since the Action Menu can be used to switch Modes if needed.
Everything in the Action Menu can have a Keybind if you want it to have one. But you dont have to have a Keybind to trigger any Actions. (apart from some way to open the Action Menu in the first place ofcourse, but that is set with the initial Setup of the Game itself and not Mod related)