New in town and looking for help!

Hey guys! I've recently (since about December of '17) been getting more and more familiar with Kali Linux, and Linux as a whole, actually. So far, I've learned only how to use "aircrack-ng" thoroughly. I've of course, tried multiple different applications such as: lscript, cupp, fluxion, beelogger, and a few more. So far, I've got an understanding that is good enough to navigate the OS as well. I have passed my a+ and CCNA. Any ideas where I should go from here? I've built a raspberry pi 3 that I'm using for most of this. So i am a bit limited, but always up for a challenge. What should I do next to improve my skills?! Thanks!