When You get some observation and specific comment upon a request of critics, it's because the artwork deserves and can be improved. I would get depressed if anyone say it's OK or give no concrete and constructive comment. In that case either You were perfect (and largely and widely enthusiastic statements would be heard or it's a half disastrous start and, politely, some generic encouragement words would be provided). So "Sursum corda!" or "Up with Your hearts" (for people who missed Latin courses at school).
Panta rei (everything flows)!
The Art you make is first and foremost for you. It must do for you and achieve for you what you "will" it to.
That horse, the beach, the clouds, the sky, they are all yours as the artist. Own it an be proud of making it what you will it to be. If along the way we can help you with your process and help you to achieve your goals, well I guess it's a good thing... but it's only a little push along the way... the journey and the destination are no one else's.
All my drawings on Deviantart Http://dannykohn.deviantart.com/
Even though you did ask for critique, it's true the art is mainly for you and for your enjoyment. If you don't enjoy it, it's just a chore. So just enjoy and take criticism with a grain of salt For all we know, you may not have been looking to paint a realistic horse!
The thing about copyright and its misuse is that there are people all over the web saying stuff is theirs when it's not, because so many photos are without provenance so people just nab them. So we could be asking for permission and that person is a con to start with. So many rules and regulations done to death.
Interestingly Enug pointed me in the right direction of the person who took the photo, so I contacted her anyway as a lot of her photos are copyrighted and she said she had no problem and even asked to see a picture of my artwork.
That is good news!
Oh God of homeless things, look down
And try to ease the way
Of all the little weary paws
That walk the world
today. - Unknown.
I think it's beautiful, and the advice that you have already been given is good, but I personally like it as is. The contrast between the black and white highlights is striking. A piece of art doesn't have to be technically perfect to be lovely to look at! (Also, you have chosen one of my favorite subjects, so my opinion might be a little biased...lol.) Keep it up!
Every artist dips his brush in his own soul, and paints his own nature into his pictures.
~ Henry Ward Beecher