What I'd like to have in the BlackBerry 10 plugin is the described incremental deployment feature below taken from BlackBerry 10 developer site.
This would make the plugin complete.
Incremental deployment of unsigned apps
You can perform incremental updates (often referred to as patching) to save time. Incremental updates are useful because the process allows you to update specific binaries and libraries without having to build a BAR application descriptor file. The QNX Momentics IDE default is to rebuild and deploy a application descriptor file to update binaries or libraries for your application. This process can be cumbersome when you need to make minor changes to a binary or library or when you want to make frequent updates.