I don't think he looks to bad, except... he looks off balance atm.
If you look at the original, Tyrannomon is built from 3 approximately equally sized segments. His head, torso, and legs are all about the same size. His knees are bent at nearly a 90 degree angle and his feet are very large and project forward to help with his balance.
Analyze the posture on the reference more and look at the legs, arms, and feet proportions to help you get him in balance. It doesn't have to be a perfect semblance to feel right.
You have a very yoshi-esque thing going on currently, with his big head sticking out way in front with a tiny tail to counterbalance it.
Make the legs thicker and pull the knees forward to under his chin. Perhaps pull his head back some as it looks like he is leaning forward.
I've got that critique twice! Will try and fix.
I had tried to bend his legs, but I'm struggling getting the perspective right. When I did, it looked like it was a side view.
The tiny tail is because of the angle. When I attached the one I have in the top-right corner, it looked too long.
Regardless, will take your suggestions and post the results. Thanks.
edit:
Put his head further back.
Both have edited legs/feet. Right has the longer tail. I've made the left 2 or so pixels shorter.
Hopefully I've sorted the weight distribution thing.
Which tail do people prefer? left or right?