My two pennies worth of preference would be to have WA extensions like DataAssist (that creates pages from scratch) as stand alone adobe air apps or similar that could then create PHP/MySQLi compatible code that can be used in any PHP site. As a result, it wouldn't matter what code editor you used then. I know that would create issues with other compatibilities for extensions that are embedded within DW, but surely if we club our heads together we might be able to come up with some solutions to overcome the reliance on DW.
Trouble is, I do like DW, always have, always will... probably... but when Microsoft or Apple makes changes to their operating systems, the likes of Adobe are in the firing line for all sorts of errors in their software, and believe me, they get grief for it. I get the feeling that this consistent updating is an issue that WA are finding difficult to keep abreast of.
So, Adobe has to update it's software, and in the process of doing so they add in more functionality to entice us to upgrade, and this obviously has a knock on effect to all vendors of extensions that are reliant upon Adobe software. OnOne that creates plugins for Photoshop has suffered the same issues as WA so they now have software that acts as both a plugin and a standalone app. Any edits you make in their standalone apps can be opened in any photo editing software. So, once Adobe updates and makes WA extensions incompatible again, the reliance on DW has been minimised. Perhaps there's a business model to follow there.