About the clip:
in the first shot there's still that moment on x54 and on where both wings turn with the body for a few frames until around x70 and then stop. It would be good to separate their movement and not have them so in sync with the body either.
I would also keep the soldier's gun where it is around -x18 in terms of height. Right now after -18 it slowly drifts up to around x40. The new re-grip after that also feels a bit slow. I would take out that drift and speed up that re-grip.
There's also something odd about that head turn ending on around -x38. It speeds up and then stops pretty quickly yet there is a moving hold to it. The combination of all that feels a bit funky. Maybe it's also accentuated by the fact that the gun is moving a bit faster during the head turn as well. It's as if the head turns quickly and then there's overlap with the gun. I would first only tweak the head and work on that stop.
The blink after the head turn feels a bit mechanical and even.
when the hand of the creature moves and the fingers move out to x151, don't have them go back. Right now they go from A to B, then back to A pose wise. It feels too even, plus the fingers go out when the head turns, then there's a pause and then the head turns again and the fingers go back. It feels all too in sync, so I would lose the second finger part. You can sell the first finger movement as the creature putting weight on that hand and the fingers flattening out because of that.
watch the base of the wings. For example the screen right one at x190. It goes down as the 2nd half of the wing goes up but then stops at x194, then moves drastically down at x197. Smooth out that transition a bit.
The lift off still feels a bit funky. It gets off the ground very quickly and it would be neat to get more separation in the body. As the wings go up, the body could go down and then when the wings flap down it can pull the chest up. I would also smooth out how the body transitions into hangtime. You have the body speed up and then come to a quick slow down around x202.
The creature grabbing the guy is better but after around x265 still doesn't feel threatening enough. There is something casual about the continuing flight path and creature movement.
Hope that helps!