Hi,
First up, great work on the new editor! Loving the tables and generally so far so good 
A couple of things that came to mind having had a play with the shiny new editor:
Footnotes
Really happy to see footnotes support make it in there.
One thing I’m not overly enamoured with is hiding the footnote at the insertion point. This necessitated clicking the text to see the footnote and having a popup obscure the surrounding text.
To my mind it would be cleaner to insert the footnote at the end of the text (markdown style) and have bear jump between the number and the footnote at the bottom (and visa versa).
This is one of the things that used to bug me a fair bit when I was using Ulysses; hiding text just feels counter productive and makes reading a note bit tedious, particularly if they’re notes you’re not going to publish.
Zen Mode
I find having the buttons embedded in the menu bar a bit jarring (but can see it helps with discoverability; still preferred how formatting was handled in the old editor). But no worries there is the zen mode which restores back the minimalist glory!
One thing that would be good to have it a preference to always be in zen mode. I don’t see myself using the buttons much and it would be great to have, and keep, them hidden.
That’s all for now!
Cheers,
Julian