The good news is you can work by just saving plain text and then viewing it in the GUI. Obsidian looks pretty but is slower and not as stable. I haven’t gone back to Zim yet but there’s nothing Obsidian really adds beyond GUI polish IMO. Obsidian has the advantage of mobile apps, but the story there isn’t superb — I have a better time piping text into it through Drafts. The iPad version of the Craft notes app is superior but it’s also much more locked down in every sense. I still use Craft though because I’m trying to simplify things these days, and I’m a sucker for OS integration.