i like the sparceness of the design. but i'm not sure i like that the feathers are rendered in the same method as the bird.
the bird seems very "electric" as it takes flight.
i think the feathers are important because that's how i knew the bird had just taken off rather than has been in the air for a while.
maybe the feathers are a flat grey (less lively)? perhaps they're dimmer colors, or drawn as single lines (rather than 2 or 3 each).
the colors on the bird on the black shirt look great. it really gives it motion.
The feathers are the right shape, but they look completely different from the bird and don''t belong on the same shirt together. I actually like the look of the feathers more than the bird. Maybe rethink the bird.
it appears that the trajectory of the bird in this version is such that the feathers are under him, whereas in V1 the feathers seemed to be a bit more behind him (which i prefer). i think this is due to the fact that the bird is a little larger since version 1 and maybe he's pointed up slightly less.
i also think that the feathers in v2 best match the language of the glowing white bird shown here. i like this new glowing white bird, by the way.