His gameplay is better, the animations are doing great.
I just have a a few sugestions:
The birdrang, if you throw it from a mid-point, the fierce birdrang takes a huge amount of energy and hits 14 times because of this effect of going towards and back, it stays a long time hitting the oponent, and if I use this along with the swingkick, i can achieve about 19 hits without the oponent could even react.
My sugestion is that you could make the return movement of the birdrang faster than the advance and the hit animation working the same way, it hits the oponent and returns faster to Robin's hand, so it could be a different way from the Batman's batrang or my Batgirl, whose batrang falls on the floor.
The dropdown and Kstomp are great ideas, is faster and allows you to attack by surprise, but this move seens to work better on the air. I say that because when i use it, i feel like I could continue the attack with normal kicks or punchs or even a grab, you could try to explore these possibilities to this move, it would be a great addon to aerial combos, and make his gameplay more dynamic.
I liked a lot the fact you could easily link normal combos and moves or hypers, all of then works fine.
Other thing, and this is something i think should be agreed by everyone, is the fact that the combos do take a lot of energy, I can win with at least four aerial combos. We could try to do the fights endure a little bit more time, so we can enjoy the gameplay more.
Anyway, the work is doing great!