Selecting and adding an image.
Today we have the following options:

What happens with selecting the size or link to? This is likely already answered in another issue.
Some of this question is answered by what we're lovingly calling "the inspector" (see work in progress here https://github.com/WordPress/gutenberg/pull/1050#issue-234159222 and also #672 ). But keeping this one open as a ticket for the image inspector settings.
This will be done with https://github.com/WordPress/gutenberg/issues/1727