It kinda worries me, for the sake of your business, that you are conflating the terms logo and illustration, and possibly logo and mascot here. And that you are creating a thing that has so many production issues out of the gate to be calling it a logo, starting with it being at least 6 colors, possibly using transparency effects, to using a hairline outline.
Be bolder and more illustrative. The head you posted is a far better look, even though that one has too much shadow detail and the outline is very rough.
Logos don’t need a golden ratio either. Yeah, it’s a theory, but only one of many.
Decals are a marketing adjunct and are usually dispersed at or near cost as a means of getting a name out there, or keeping your name in front of existing clients. While I might actually purchase something with a band logo on it to support the band, I’m not so sure I’d purchase someone’s company logo (I don’t wear branded clothing either though.) A unicorn sticker that is colorful and cute, pretty much a dime a dozen on Etsy and some of those are printed on cool sparkly media, LOL. What makes yours unique? And with that skinnnnnnnnny black border, what is your diecut path gonna be? Cuz there is no spot-on registration when it comes to die cutting things. That border will absolutely get cut off in places… Pulling bleeds for an edge cut on that is gonna cost you some system time too, if you don’t do it. Or you could put it in a boring circle or square.
Think Finishing before Beginning.