Ok, I have a soft spot for Bruno Mars. Sure, this one is a lot of “noodling on the piano being sad about getting dumped” and isn’t that Adele’s shtick? But listen a little more closely and you’ll hear far more complex harmonies (seventh chords, secondary dominants, and deceptive cadences oh my!), and actual use of volume beyond the master fader.
Edit: Sorry there was a problem with the embed. Fixed now!
But really, the best video of his is this one, an “alternate” version of the Lazy Song featuring Leonard Nimoy.