Creating an alternative Piano Roll

[dodobird]

I'm interested in developing an alternative piano-roll plugin for Reaper. Among other features, the Play Cursor position of the plugin must be synchronized to the main Play Cursor position in Reaper (like the normal piano-roll in Reaper).
Would it be possible to create such thing as ReaScript plugin? Maybe a Reaper extension would be the best way to do it?

Any thoughts and advice would be greatly appreciated.

Oded.