Congrats!
Well I'm not really Tim Cain's fan. I only "just passing by" on YT and happen to watched a lot of his videos.
I'm a big fan of self-improvements and life-long learning. So anything that seems to be interesting will be munching by me :D
Even my game built on the theme of "Sorcery Tech" wasn't influenced by Tim's games, though some people told me about Arcanum and stuffs.
The idea of "Sorcery Tech" actually originated from my personal interest in both sorcery and technological stuffs. Cyberpunk genre is one of my favorite genres. So many ideas within cyberpunk world could be explain easily by changing the law of the universe from physics into sorcery.
I originally worked on generic fantasy world with my own spins, but I wasn't that enthusiastic about it and didn't have a proper vision on the idea. So my project "Arcane Horde" seems to comes to the end because of this. I planned to use stuffs that I created within Arcane Horde and adapt into the current jam project "Abyssonance". Well they're actually easy to adopt, since they're purely gameplay systems which we could called Arcane Horde as another tech demo that I made.
I'm glad that you could easily get the context of the video I made. It's something that I think many experienced game developers should have some ideas working on it or at least have seen someone doing it.
I personally think that the "Horizontal slice" or I called it as horizontal build, is a good way to start working on the game. Maybe we don't have to make the entire game but making horizontal build for the vertical slice would be a good start in any kind of projects.
Then if we're not sure about the game scope just yet, maybe try to merge stuffs together into a bigger group like player + stats + items = player parameters. Maybe we could make bigger groups depending on the contexts and scale we're going to compare. Afterward we could make the horizontal build in the form of miniature which we could easily scale up on paper and use them to estimate the real scope.
I'm not sure what do we call this technique, but it's when you're far away and use a ruler with a hole to estimate the height of a tree by calculating from the distance between you and the tree...yeah maybe using Pythagoras's formula to solve this in order to get the estimated height.
I just adapted the concept into estimating the scope of the game, which will be useful especially when you're working in a small team or even solo.