Enjoy your stable systems while you can! Learning comes through solving problems as they come up. It's a good sign if you don't have to.
Need some new functionality? Figure out how to set it up. Encounter a bug or issue? Troubleshoot and fix it. Functionality that you want doesn't exist? Time to program it yourself.
You can also start customizing (ricing) your system as you wish. Take a look at unixporn style communities for inspiration and advice.
Lmao yes technically correct. The grapes aren't doing anything new, they're acting as a microwave resonator which makes some very interesting plasma physics you can do with a grape in the microwave. However, this is not a new phenomenon and there are much more convenient microwave resonators you can build out of metal.