Nice shots... you have some great subjects and a nice eye for composition.
Could be just the weather, but some of them have the "vaseline" look, maybe some quick PP with levels and sharpening would do wonders.
Not sure if you are ok with editing your pics, but here u go:
i think the copyright it's way too big and becomes really distracting... after the 2nd picture it was actually the first thing I looked for in the picture, i understand the need for copyrighting our work but remember it's not really suppose to be there...
I think that in #3 the selective coloring isnt working well. Maybe if you put color to the second riders coat as well, that might do something for the picture.
You said, 'a couple of pictures'. You lied to me. I feel deceived.
I agree with someone above though, I think the mist hurts more than it helps in this case. That's just me though, do what you wish, it's your work after all.