I recommend greatly expanding the space of problems you can solve, by exploring the world of hardware, signal processing, etc. It's usually a good thing to be a generalist.

Try out GNU Radio, it can use your audio I/O for signal sources and sinks. You can learn about DSP, complex signals (with I and Q) and develop an intuition about a new domain of computer applications, just for fun.

If you feel like spending some cash, you can get a USB receiver kit for about $40 and explore the world of radio.

You can also get an Arduino or a Raspberry Pi starter kit, and start doing hardware things, to get acquainted with that world.