The other thing that helps a lot with touch is to use windows built in magnifier app.
Zooming in to a small plugins interface so it now covers the entire screen is extremely useful. The controls become much more adjustable, allowing real time ultra fine settings.
Setting fiddly envelopes in a synth is joyous when you have that tiny little window 14 inches wide by 6 inches tall.
I use a large 18 inch tablet (Dell XPS18) without a keyboard and mouse. I position the tablet over the comtroller/synth, tilted flat. Getting rid of the mouse and keyboard has completely changed the "feel" of using Sonar - in a good way.
Its gone from a Computer DAW to a "instrument" in its own right.
Features like the onscreen keyboard and the multi-touch eqs are great. Brilliantly implemented.
I think there are software designers at Cakewalk who really understand where Cakewalk could go with this, but I suspect there are also designers at Cakewalk who have no conception of what touch is for.
The result is Sonar's touch implementation is exactly 50% Genius/50% Stoopid.
Seeing as Dell and other manufacturers seem to be phasing out large format tablets, maybe the way i use Sonar will always be a freak oddity.
Unless of course Apple releases a mega ipad and then everyone will love it.