I like the bg. The walk cycle has personality, but it needs work.
- Looks like you just repainted the forward foot on the further leg, it extends below the floor. Redo it properly.
- The body "hop" (vertical movement) is at the wrong timings.
On this forum, you'll find a link to a walking tutorial, often posted, much better than the one Fizz pointed to. Do a search. Also, look at how people walk, best way to do things right is use reference and pay attention.