I am constantly thinking "If I could only write a plugin for Hype, to do this or that"
- code completion, code folding and inline syntax warnings. Or simply when you double click a bracket it shows you it's partner.
New types of event actions in the inspector.
bezier pen tool, which many of use have request in one form or another..
I have actually written a text replacement app for Hype, that allows me to type a keyword in Hype functions and my app will expand to the matching stored text.
Here is a quick video of it.
( I am actually, trying to find the time to re write it, as although it works really well, some of the storage methods need changing.. )
There are problems with the idea of plugins that directly tap into the code of an app to alter it's display and functions as you describe
A badly written plugin could cause havoc with Hype where in the end the Hype team would have to possibly waste a lot time trying to put out the fires.
Also how many of Hype uses could or would write such plugins.. would the effort of introducing a plugin framework be fully realised by us the users!
Update. Put the video on my own site due to dropbox being .S..t