Hello,
My Suggestions: Make a deal with the various multi-touch app developers to port their apps into Sonar X4. Adopting any of these products will make Sonar the top multi-touch DAW and a lot of musicians very happy.
1. Call Liine
https://liine.net/ to design their Lemur apps to run it Sonar X4.
2. Talk to SensoMusic
http://www.sensomusic.com/usine/to incorporate Usine Hollyhock Touch Screen Edition into Sonar X4.
3. Contact AudioMulch
http://www.audiomulch.com/info/what-is-audiomulch#play-it-like-an-instrument Persuade them to make AudioMulch multi-touch friendly and then let it run in Sonar X4.
4. There are many music multi-touch iPad apps that can be ported to Windows. Some are midi controller apps and other are synth apps. Why not contact some of the top/best iPad app developers to port their apps for use in Sonar X4?