I've come to the conclusion that touchscreen devices have a lower information throughput than traditional desktop machines. Relative to a mouse, the touchscreen is inaccurate, unreliable, and (using it) blocks your view more. You can't rely on there being a hard keyboard, and if there is one, you can't rely on it being big and comfortable enough to use at high speeds.
So it's hard for me to imagine, even in principle, how you'd port something like Starcraft. It uses almost all of the desktop's information throughput -- two or three mouse buttons and most of the keyboard keys going like mad the whole game -- and you just don't have that kind of bandwidth on a touch screen.
I would love to see a Real Strat on a touch device -- not just a lot of tower defense games. But I think you'd have to do a lot more than port what we have. You'd have to go back to the beginning, back before Warcraft, when they were still figuring out how to make the controls work on a PC, and reinvent the genre for touch screen.
Touch screen games seem biased toward the turn-based and the scripted, rather than the real-time and manually controlled. Perhaps, with a lot of scripting and game redesign, RTSs could survive that transition, but I think they'd come out looking pretty different.
I can definitely see playing a quick starcraft game on my tablet as a fun little diversion while I'm on public transit or something.
Problem two: Starcraft is not the best "quick game for a fun little diversion". Maybe I've got the wrong idea here, but IMO RTS is the Monopoly of video games, and I don't play Monopoly on the bus.
But I get your point.
We used to play Starcraft as our after lunch activity in the reddit office. It was a great quick diversion.
In Starcraft most matches are decided in 15 minutes. That's one of the reasons for its success.