I know, I know... MPS 1.0 hasn't even been out for a week yet and here I am making a wishlist for future versions. :-)
I am hoping this thread can be a place to throw around crazy or not-so-crazy ideas about what people would like to see in MPS, and discuss what people think about them. Feel free to join in!
The big one I'd love to see implemented is context-sensitive help for nodes. I think MPS has some really good opportunities to provide excellent context-sensitive help. MPS could add a Help/Documentation tab to each node in a language, to allow language authors to provide help that the built-in MPS editor could then make use of through tooltips, F1, code completion, offline documentation, etc...
What other stuff would people like to see in MPS?