Regarding the second improvement in your list, I was using Quick Launcher with my tohkbd, it was a great combination and allowed doing part of what you describe (just part of it, i.e. launching applications). I was leaving it permanently open, and when I needed to open a new app, Alt+Tab, "em", Return, boom here's your e-mail app maximized.

It worked even for apps already open, but in that case Alt+Tab was just simpler. You can also set shortcuts to several applications on F1-12 if I remember correctly. Quick Launcher was one of them for me, so I didn't even have to Alt+Tab first, I could just use the shortcut for QL to bring it to front and start typing. I barely needed the other shortcuts.

To be honest I seldom use Quick Launcher without a keyboard, it's often just easier to use the home screen or launcher. With a keyboard, however, it already provides a very good keyboard experience with Sailfish. Feels like having a Super key and a Linux menu with a search field.