I think this is great if you use annotations only sparingly. On the other hand, if you have a complex preset with lots of remote controls and each one has an annotation, it can become really cluttered. Maybe if you can toggle it on and off.
Could it be provided by a VST or something else reasonably integrated with Bitwig?
i’m only aware of that LV2 plugin i’m referring to, but at the moment Bitwig does not support LV2 anyway.
There’s also MNotePad by MeldaProduction which is free. The problem is that you need to press shift+spacebar if you want to enter a space because spacebar by itself starts/stops playback. So a built-in option would be definitely prefrable.