Because I'm not a fan of the current writing experience I experimented with improving it:
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What I did:
* Increased the font size to largeFontSize (1.2 * regular)
* Limit the editor with to roughly 70 characters
* "merged" subject and text
** I know we initially separated the two on purpose, but I'm quite happy with the result, and am not too worried about the "problems" this creates of the formatting only applying to the text and the attachments belonging to the content.
* white background instead of grey
** the only problem with that is that it becomes non obvious where the textbox is if there is no text yet. Could be helped with a default text just like in the subject.