Wow thanks for the speedy reply!
Would be nice to have a "duplicate this thing I'm selecting!" in a perfect world. I don't envy that the keys need to work for 3 platforms at once, on the Mac Apple+D is de facto standard for duplication in Finder, Unity. It's deselect in other software like Photoshop and Illustrator.
Ah, I'm checking this doc now: https://github.com/bjorn/tiled/wiki/Keyboard-Shortcuts (probably should have given this the once over before posting!)
I guess it's something to consider, personally I don't like that there is no shortcut key in Photoshop for toggling contiguous, so I'd take a shortcut over that for this any day.
In general, it would be nice if the shortcuts were more harmonious to other applications that are used in conjunction to Tiled in the pro & indie environment (as a lot of these tools are now free or low cost, like Photoshop which is now $9 a month).
Things like G for fill, M for marquee etc. are muscle memory for their wide use in most apps, but need to be re-learned for Tiled in hardcore use. (not that I'm saying Tiled shouldn't be it's own beast! But GIMP is not widely known, so drawing from it's own particular set of shortcuts might alienate a lot of users)
Maybe icon tooltips could show the shortcut keys to aid in learning? "D" for random mode for example.
Anyway thanks for the reply!