Just like the title says- is it ideal to put off learning digital concept art in order to get a basis in traditional drawing first? I'm doing a 6-month challenge with my girlfriend to learn and develop my concept art skills (which are nonexistent right now) as fast as possible, so it could be easy for me to pick up some initial bad habits if I don't stay consistent. What would anyone recommend?
Very cool, a challenge is a great way to stay motivated! If you're looking to start the Concept portion of this site, I'd recommend diving into the courses in this order:
https://cgcookie.com/flow/introduction-to-digital-art
https://cgcookie.com/flow/introduction-to-traditional-drawing
And then pick any of the misc. Courses or Tutorials that sound appealing to you. And don't forget to do some exercises, those are the fastest way to improve!
I would recommend doing both at the same time. A lot of learning within each will carry over to the other. So don't feel the need to put one on hold while developing the other. Instead you should focus on drawing often and with a critical eye. You can still have fun but be sure to look at what is "incorrect" with your drawing and work to improve it. Do this enough times and you're sure to see improvement!