so like, the profile pic you have on the main list. i think that would look better on the shirt than the whole penguin, but that's just my opinion... but cute idea
It's not really funny enough to good enough to sell. I think you should go back to the drawing board. However, if you want to improve this, hand draw the penguin first off. The penguin seems to be made of shapes. And eliminate the text reliance. Shirts are visual humour, reading detracts from it all.