Looks great so far 8D Especially as you normally draw canines, I see some people give them really long muzzles xc
I'm no expert, but here are some pointers:
-As others have said, the ears should be rounder.
-Lions' back have a slight curve in them.
-Legs are slightly shorter and 'thicker'
- They also tend to be slightly more 'rotund' and, as most cats, they have a kinda 'saggy' bit of belly usually from
the end of the ribs up to where the body ends.
Here is a picture of a lioness next to your drawing so you can see what I mean ;3
