To answer the question, it's totally possible, and as I'm typing this I realized there's a stupid easy way to make that happen. Also, in the next milestone, you'll be getting basic unit actions, which means some basic-level unit UI. So you'll clearly see that you have a unit selected because an associated panel will pop up. But yes, I think I can make a really simple unit highlight to make that even easier.
(I originally didn't make one because it was outside the scope of the first milestone, but it's a good usability win with minimal effort, so I'll add it onto the second milestone.)