Rename "Post reply" button when quick reply is enabled
When you have quick reply enabled (as everyone should by default IMO, it's a mandatory forum feature these days), you get a little button called "submit" - and below it, a much more obvious image button labelled "post reply". I've lost count of the number of times I've typed in a quick reply and then hit "post reply" instead of "submit" and lost my reply. If you have quick reply enabled, the button that takes you to the full reply page should be relabelled to something like "switch to full mode".
(A better option, as per the Wowstead forums, would be to remove "full mode" entirely. There's no value in having a separate page for posting - just put the full reply box where the quick reply box currently is.)
Usability, yo :-)
This is not currently planned to be included in a development cycle, but we may revisit it at a later date.