Not on purpose, I can assure, but I'm a big fan of Samurai Jack and when designing DL I knew I wanted him to be all black regardless his shape. First designs were very bulky and nothing near what he now looks like, and the armor had much more detail... I just simplified the design to the max.
I mean I see some similarited but by no means is there a rip-off. If anything I say the little guy is more of a homage to Aku. I can see some similarites but your's is definetly different and unique enough that he dosen't seem like a blatant rip-off at all. I actually wouldn't mind chatting with you either through IM if you'd be willing to some time.