Yes, the hat was intentionally shaped, not many hats have a perfectly flat brim. The reason I removed the beard was because of how distinctive it was. The original skull picture is someone else's monetized property (I provided a link below the original picture). As such I went through and made my own skull *based* on that one which is a bit simplified to avoid copyright issues as this was specifically brought up in the banner requirements. I feel that the picture is safe to use at this point as it is my creation rather than me simply recoloring anothers work.
As for being grayscale, the M3 banner reward is grayscale, but there are also rewards for the Ark Leige which seem to imply that there is the opportunity for colored banners and logo's as well, as such anything I design will start with color and be turned to greyscale if needed. To me having the black and white skull with the red eyes (much like the reaper sketch I did earlier) makes it pop out a lot more.
EDIt: Also rather than a beard I was going to give the guy a cup of tea...the skull really looks like he could use some Earl Grey (get it...get it...)