This is a great animation. I can see where you took the critiques from your last loop and you’ve improved it a lot! I also love the design! The colors and design choices you came up with really hit the mark with referencing Australia.
I’m going to get down to brass tacks though: it doesn’t move all the way like a kangaroo (but it's getting there!). It moves like you might expect it to move if you haven’t actually spent time watching a LOT of videos of kangaroos. It moves like a wolf or cat might move if you stretched it until it looks like a kangaroo – if that makes sense. Let me explain.
First, kangaroos almost never bob their heads. They’re jump is actually quite a lateral movement and not so vertical. Any vertical shock absorbing movement (which is currently showing up in the neck), is taken by the back, between the shoulder and hip. It doesn’t bend up and stretch out, like a typical four-legged animal that’s running; it’s more of a slight rocking movement.
The legs don’t bend so dramatically in the knee, either. Once again, it’s not like a cat or dog jumping. The kangaroo’s knees don’t bend on impact for shock absorption, as in other animals. Instead the toes and hips take most of the shock. As the toes strike the ground, the chest is at it’s lowest tilted point and tail at the highest and it’s thighs are actually moving downwards/ away from its head as its strike. The deepest bend in the kangaroo’s knees are actually on the back end of its stride, when it needs to lift its ankles so it can swing its toes back to the front without tripping. The movement of the legs is much, much wider – they really toss those suckers out in front of them and out behind when they’re on the go!
All in all, I have to say GREAT job though. It’s a hard animal to capture and very different than other animals. I would really encourage you to watch lots and LOTS of videos of kangaroos. Challenge yourself: try to animate as FEW lines as possible to get it to look like it moves like a kangaroo. If you can get the movement down, you obviously already know how to do the rest!
I hope this was helpful (I’m not great a fluffing up a bunch of stuff when people are asking for a critique.) and that my criticism was constructive for you.
Good luck! ☺