You're for sure on the right track! I agree high tier 3 for now. I would focus more on lighting rather than manes and tails right now. I quite like your work for manes/tails on the first three pieces and the last one. I do agree with the comment on body prep although personally I'm not a fan of the smooth looking bodies, but once again that's personal preference. I would suggest working on the blending bodies that are a little pixley or undefined (like the blue roan in the field) though. Like Ambrosia said you have a LOT of potential, personally I love the second piece (minus the added animal but that's just personal beef with other animals lol). If you'd like some guides on more specific parts of making art I will gladly PM you the list I've made!