Hello,
It seems that this thread is the right place to get answers on the missing features I used to love Evernote for, adding to the things mentioned above, here's my list:
Tags: are harder to use and no longer serve their purpose.
I can no longer select multiple tags at the same time from the tags sidebar. Once I click on the tag it closes the sidebar and applies a filter based on that one selection.
Previously, when I select a tag, it highlights all the combinations (which was very useful).
I have sub-tabs, the buttons for expanding and collapsing parent tags are gone
Previously, in the notes list, it shows only the tags applied to the notes in the notebook in question. Now (after going to the filter menu then to tags sub-menu) it shows all tags
Global shortcuts are all gone: and no information if they will be brought back
Some of the attachment extensions are no longer supported: e.g, tiff (no longer supported so I lost so many of my images), some 'big' images are displayed as attachments not as images.
Share: no longer connected to my contacts, it used to give suggestions from my contacts once I start writing an email address or name
Sidebar: not showing the notes count (hopefully it will be back with the preferences)
In-App (classic) Links are gone: I know it's mentioned above but I had to repeat since I heavily rely on it to link notes from other applications