MPS gives the feeling of working with "structured" spreadsheet, e.g. editing the sheet data compliant to a defined schema, which is IMHO a really useful feature missing from spreadsheet applications. Is it possible (or would it be possible) to have some "real" spreadsheet functionality in MPS?
A typical spreadsheet usage example - calculate a sum of N integers.
It is possible with MPS to define a model that is an array of integers, and define an editor for this data structure. What is missing is - how to define anoter model element that will be the sum of that array and to have it re-evaluated every time the content of an array is changed?
Spreadsheet IMHO are great in a way that they provide instant results without the need to generate code/compile/run resulting program. It would be nice to have this kind of integration - editing models in MPS while runnng "the program" already difined in MPS. You can interpret is as "on-the-fy model translation and execution"