Great thread, discussing the big problem of Android webview. Well for those who want to try crosswalk, good way to try is to use Intel XDK. You can package your Ionic app with crosswalk without any command line interface. Simply import your Ionic app’s www folder in XDK and use “Crosswalk for Android” option under “Build” tab of XDK.
Just use Ionic to develop app and use XDK to build your app for Android.
Pros - Smooth interactions like as if you are on iOS.
Cons - App size increases hugely as chromium based webview gets added to your APK. my app was 2 MB earlier, now with crosswalk APK is 18 MB and once app gets installed on phone, it takes around 50 MB 
Regarding support for 2.3, I think its important to support it as highlighted by @Robin but at the same time I agree with @max viewpoint too that supporting 2.3 will be a waste time and effort as it just hold 14% market share and anyway its pie will further reduce in some time, so supporting a going platform does not make much sense.
Regards,
Gaurav