Oh, how cool! So you're a concept designer/graphic designer for the LEGO Group? That's got to be an amazing career. I wish I were talented enough to get a job like that.
I'm not sure how far the sets would have been in the design process when you were developing these concepts, but I think it's cool how the spinner crown motif on the torsos matches the set 70726 Destructoid. It's a bit of a shame that the final designs didn't end up using the LEGO robot arm and leg pieces, but I suppose that makes the finished Nindroids more consistent with Zane, our previously-established Nindroid character.
The final Nindroid designs are very elegant, and it's neat to have Ninja (of a sort) as both heroes and villains in the series for the first time. It's good to see that all these concepts paid off in the end!