I'm going to be the voice of dissention. Yes your photos are good. But they really still look like photos. They don't look like cover images. And there's a difference. I also agree that the back photo is far more compelling than the front. Here's why. The woman looks interesting, the people on the front look very much like a group of stunt people hanging out during a rehearsal (would you believe I am very familiar with what that looks like
?). I don't see a group who battle together (I kind of assume that's what I'm looking at). I see people posing for a photo with props. Also the forest is overwhelming. It's too much to look at. See the tree/bush in the foreground, it's just as in focus as everything else. Our eye isn't being directed anywhere.
Second, you can cut out the woman on the back and superimpose her onto a more compelling background. Right now what you have is a photo with some words over it (I realise you've actually done some tweaking in photoshop, I can see that, but it's still not enough). This is what makes a book look like it didn't have a real designer work on it. A cover has multiple layers and elements to it, not just two. And our eye is used to seeing that. When we see something this straightforward, we immediately think "this isn't a professional cover".
Let's look at some covers that use photographs:
Here the focus is on the whole picture, on the location, the time period and the two kids have their backs to us. The whole thing has been given an oldy-timey treatment. The key is that the people aren't the focus of the cover. The setting is:
http://1.bp.blogspot.com/-T3XAXU5OiPs/T48E6RUSW_I/AAAAAAAAPOU/Ohp9nwFcc5g/s1600/sarahs-key.jpg
Here we have a single woman on the cover in a setting - but the setting is simple and fades into the background, it is secondary to the person. Further we can't really see her face, and we have a sense of a misty wistful mood. You can see the saturation levels have been played with:
http://image.guardian.co.uk/sys-images/Books/Pix/pictures/2008/07/29/Kennedy460.jpg
Here you have a group of warriors (sort of, technically it's a painting but it looks pretty close to photographic). Note how in this case it's a composite. The people are placed onto a different background:
http://1.bp.blogspot.com/-4Hx5yPK3PAI/UC7VdGg4g5I/AAAAAAAAI4Q/90KhQvUOfHM/s1600/Trickster.jpg
In fact I'd suggest you google fantasy book covers and see if any look like yours right now. None do. Even the photographic ones.
I hope this doesn't read harsh. This is no way is meant to put down the photographs themselves, which are well staged and well taken. But like I said above a photograph isn't automatically a cover. I realise you are probably very attached to the photographs (I know I am with ones I take), but I'd suggest possibly even going with an object on the cover, no people at all.
And look, ultimately my opinions are just that. Further if you keep the images as is, I think it will still convey what kind of book you have written which is the fundamental job of a cover. But you posted here for opinions, and those are mine. Oy. I really hope all this isn't too harsh. It's truly just meant to be constructive
.