I don't think you necessarily need advanced bitsy skills to host a jam, especially if you're doing an unofficial jam. Mostly you just need the ability to get the word out and willingness to be the one to press the "Create a Game Jam" button. And if you posted about it here in the community, I'm sure you'd get a good turnout.
Unfortunately I don't know of any specific jams that match what you are asking about, but if you look on itch.io's jam page for jams with no engine requirement, I'm sure there will be something that will catch your fancy.