Cosmetics.
Let’s offer paid cosmetics for users of your instance. Animated or custom banners, posts, new themes, etc.
It’s a model that works really well for Discord and League of Legends. Instances offering to sell aesthetic luxury to their user base could work for Mastodon too.
It’s non-invasive, it’s optional, it’s a great addition for some people, and it allows to raise funds to keep the hosted instances up and running.
Do you think it’s viable?
I personally couldn’t give a crap about those kind of things, I definitely wouldn’t pay for it. Mona looks great and is already customisable enough for my liking. Some other apps have even more visual customisation.
If I wanted a custom theme in my web browser I’d run custom CSS, like how Bird UI works. Or just use a service like elk.zone and I wouldn’t have to faff around with custom themes/code/plugins.
But sure, I don’t see why you couldn’t do this. It’d be best done via plug-ins for Mastodon, not per-instance. Then people can off plug-ins in some kind of marketplace. You pay for the plug-in, it installs into Mastodon, and you can manage your current plugins from your Mastodon preferences.
Yeah, why not. If someone wants to build it then there’s no harm in it existing.