Honestly pretty much what Dev_J said.
The art is fantastic, you are truly talented. The video was a tad longer then it could have been. 3 minutes for stuff like this is usually a safe timeline. Commentary in my opinion isn't needed for this video, unless you do a How-To video, but at least make sure to have some details of what equipment you used in your description page. And ya your end card is a bit basic. What I would do is somehow design something that uses your art style as the end card. For example, have a the lion you just did, and above his paws, and in front of his face have a *recommended next video* or playlist. Also, maybe drawing a frame in your art style to put all your social media details in. Maybe even draw the icons and superimpose them on. Something like that. Hopefully that made sense.