I also develop a note-taking app [0] and so far I've chosen the side-by-side live preview approach, but it's interesting you're trying to make it work with only the editor.
I'm wondering how would you go about keeping notes with many links readable? For example, in this note imported from Wikipedia [1] the left side is hard to read while the right side doesn't have this problem. Some users have also been importing entire web pages, which are a mess of tables and links. They render fine in HTML but are not readable in Markdown.
I think link in edit mode is OK. I used the conceal feature in Vim to hide the URL part of the link when I used Vim to edit Markdown before. But I found that it distracted me when I moved the cursor above the link, the URL part showed, and when I moved the cursor away, the URL part hid. I think it is better to show all the text to the user and use syntax to highlight the outline of the content.
About side-by-side live preview, I hate the feeling of moving eyes left and right frequently and try hard to keep track of where you are.
I'm wondering how would you go about keeping notes with many links readable? For example, in this note imported from Wikipedia [1] the left side is hard to read while the right side doesn't have this problem. Some users have also been importing entire web pages, which are a mess of tables and links. They render fine in HTML but are not readable in Markdown.
[0] http://joplin.cozic.net
[1] https://i.imgur.com/Ah62JRI.png