Obsidian alternatives

I'm still working my way through Flight School since the newest release of Flight School 2.0, but I must say it vastly exceeds my expectations. I'm fairly new to Obsidian, PKM, markdown, etc. but I've already learned a tremendous amount from Flight School. I feel like it's definitely accelerated my passion to become a better and more efficient power user for my Mac and for Obsidian. I highly recommend it! Additionally, after watching many of Nick Milo's YouTube videos and going through Flight School and his LYT vault (Linking Your Thinking), I can easily tell he is a highly educated young guy with tremendous potential. The only downside I can think of is I still can't figure out his riddle 😡