Coming at you from #1957276: Let users set the block instance title for Views blocks in the Block UI . Here's a follow-up from that issue:
"Recent content" block in HEAD:
"Content" block created via adding a block display to the Front page view:
...and with Override title checked:
The one remaining visual problem here is the machine name field does not follow the standard pattern (also, that extra fieldset around the title is something non-standard we don't do elsewhere). So, would it be possible for this instead to look like so (standard machine name pattern with text field simply disabled):
...and with Override title checked (field becomes non-disabled, description shows up):
...because then there is pretty much literally no difference between the two and so all UX concerns around Views vs. normal blocks are addressed.
And actually, now that I think about it, that dynamic description thing is probably more trouble than it's worth. So it'd just be the checkbox toggling the disabled property (and possibly some CSS; Firebug didn't seem to change it to grey when I did that) on the text field then.