The camaraderie, friendships, seeing lots of neat rockets, FLYING the rockets, all great aspects of this hobby. And I sure like to do contest flying too.
But since the question is what I like the MOST, I have to go with what is at the core of my interest. Designing models and seeing them fly successfully. I do NOT like the building, but it is a necessarily evil step between the designing and the flying. And sometimes the designing goes sideways mid-build as some issue comes up during assembly, or after-build when a design flaw is discovered in test flying, requiring a design fix and more testing to confirm the fix works.
Like right now I have a design project underway, close to a prototype test flight very soon. I have not spent nearly as much time building it as I have THINKING about it (first thought about building this model over a year and a half ago……or in another way about 46 years ago) And once I wanted to finally begin the project and start to build….. lots of preparatory time to really do that actual design, determine all the components needed, figure out the build sequence, how to address some specific design detail that had been a general concept to be finalized in more detail “now” before the next step in planned assembly could be planned out, and so on. Lots of those general concept things that had to be figured out.... even where to make it most fragile so in a hard landing/crash, something "easier" to fix would break rather than risk breaking a much more critical and harder to repair part of the structure. I will say that the nitty-gritty design details like that are not a lot of "fun" either, projects like this are always more fun to think of in the big picture sense than the very specific details.
Ironically this particular project isn’t rocket powered but it’s a model of a “rocket”, that will fly.
So, I’ve gone past most of the “design” portion of this project, into the being part which I wish I old press a button to do (But I do have to admit that while I do not like building, I do appreciate that it is something I built myself, once it is done. But in the middle of mid-build….. ugh). And hopefully, the payoff end of the project later, successful flying of the design project. Since it is not fun to design something that in the end does NOT work out, or maybe works technically but flies poorly.
What the heck is it? Well, I’ll start a proper build thread about it on TRF soon, and have mentioned it a bit elsewhere. Here’s a pic as of today, with a dummy profile “upper part”, sitting on top of the lower part of the model that has all the critical design parts that will (hopefully) make it fly. So, a Quadcopter, electric motor and propeller powered, but one of the most important “rocket vehicles” in history.
So, sure, I could buy a Star Wars Millennium Falcon Quadcopter, for example. But what I have wanted, since I got into model rocketry in 1970 and came up with an “ultimate dream model”, was a model of the Lunar Module that I could fly by R/C, hover, and land. For 1970 that was an insanely impossible model to even think might be possible to do. And while in theory a extremely fine-throttleable hybrid for hobbyists could maybe be made, lots of hobby dollars and time, and someone else’s expertise to make that happen someday. But what was even more farfetched at that time was to be able to have R/C small and light enough to be able to control such a model. And most critically have the ability to keep itself level, using technology that in 1970 would have cost millions and weighed dozens of pounds (for the Gyro-based guidance system itself) instead of 15 grams for $30. Back when a “computer” would require its own room in a house, not fit in your pants pocket or on your wrist.
So…. to end such a long answer to such a great short question…… its the combination of designing something of my own, that ends up flying well, that I like the most.
Sometimes it’s complex stuff like this new project…. (temporary dummy profile on top, to be replaced by scaled-up cardboard model patterns, printed on thick poster paper, cut out and assembled for proper 3D shape)
And sometimes it just takes a few minutes of designing and “building” something simple. Even when the designing part is more like seeing something in a store and realizing: "Hey, that might be a pretty good conversion for Flying Saucer"