This is just to encourage you to experiment.
Ideally, you can build something, but experimentation does not have to mean building. As I have found out (the hard way!) there is still a lot we can do in our great hobby just by observing.
Propagation is a great way to observe, whether it is on any band. Another is to try a new mode, maybe ATV or FT8. Perhaps try QRP or satellites.
What is so great about our hobby is that it can be enjoyed in so many ways. Some enjoy chasing DX whereas others just enjoy a good ragchew. I can only speak for myself by saying that my greatest fun was when I found out something new and challenging.
One thing I have learnt time and time again is there are no experts! Those who claim to be experts are often proved wrong, peddling myths they heard 40 years ago. Observe!! Over the years I have found out several things myself. One of the joys is finding out yourself and not accepting conventional wisdom.
Two things stand out for me. One is I am convinced there is some sort of chordal hop E layer propagation. I have not (yet) seen this accepted. The other is how effective earth-electrode "antennas" in the ground can be. Over the last few years, these are being increasingly used by amateurs at MF, LF, VLF and ULF.
What myth are you going to disprove?