Some kind of interface I would like to see more is a mix between arbitrary text buffers (say, like a text editor), and a command line interface that could display inline graphics.

What I mean by "arbitrary buffer" as already been implemented at least once (I think acme works similarly, albeit not sure). Any bunch of text can be a command, and it's not the system that will tell you (with an error!) wether what you entered is a command or not. You can run "any text" with a single, simple action, and YOU, as the user, decide what is a command , and what isn't.

The reason I don't use that editor is because it is hard to compile, and doesn't work well remotely (require X.org).
I'd definitely be happy if it was the norm though!