Try 4230 on your baritone ukulele, a Dadd9 with the 3rd on the lowest string. Sounds nice on my tenor guitar (tuned d-g-b-e like a baritone ukulele with steel strings). Add9- and sus2-chords are two of my favourite chords at the moment actually:-)
I am noodling around a progression that goes like this: 0022 (G5) 0230 (Dsus2) 2030 (Em7) 2002 (Emadd9)
That's amazing:-)