It can be useful to have a feature to being able to easily change from an user account to another.
It can be useful to have different users for different communities.
Also, it can be useful to see a list of features that you have already choosen to add sometime in the future, so maybe users as me will not ask again and again 
This ‘feature requests’ forum is that list
‘Already chosen to add’ is a high bar — it depends on so many things that I have no control over. For example there are features that should exist but the implementation is complex enough that I can use the weeks / months that it would require in dealing with much more urgent things. Features that require backend / graph changes are generally that way. When you think of a feature, you usually don’t know this when you start to implement, so there are definitel stuff that I get into, and sometimes have to back out because it becomes obvious how many corner cases it creates or how complex it ends up being when implemented as part of the whole system, and so on.
I might at some point try to create a very rough roadmap and post it somewhere, but things are too fluid right now to even attempt to have such a thing, and likely will be for the short/mid term future. My main concern right now is to keep the network up and make sure everything works as usual. I’m also collecting user feedback, feature requests as well.
I like one user per computer or a maximum of 3 usernames per account, otherwise, the platform would be inviting spammers and paid shills on the network.