Of the ones I think are most successful, it’s clear that something that has a separate icon (usually placed to the left, like theoze’s ‘pencilshirt thingy offers more versatility, but I’m not sure there’s a magic one yet that suffers huge reduction and standing alone (like a favicon) that 100% does the job. It could just be one that’s shortlisted or in the final that needs some final adjustments/tweaking.

In comparison, the one in the final that’s a little tag attached to the ’s’ of spread (can’t remember the name, but it’s on a black background and the tag is orange) doesn’t have that standalone icon – if you showed it without the ’spreadshirt’ text it would make no sense (as of yet).