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I suggest leaving out the word HDR from your description and let the images stand on their own. Mentioning HDR puts the HDR police on full alert in this forum.
Oh, I like no. 3 followed by 4.
Since the OP titled his thread "Trying for more realistic looking HDR" - I figured it was OK to comment on that aspect. Somehow I don't think leaving out the letters HDR would have anyone believing that some of these were a result of anything but HDR. You can spot most Photomatrix HDRs anywhere... they're dirty.
I like the composition of these photographs, especially the second and the last. But when it comes to blending for dynamic range, there's just something not right about the muddiness created, especially in the foregrounds where there should be deeper shadows.
In #1, the reflection is brighter than the sky - this does not look natural. Maybe bring the exposure of the foreground down a little to create amore natural look.
In the foreground of #2, it looks like someone squished their thumb all over a newly inked and still wet print. The sky seems pretty natural looking, but the foreground exhibits that Photomatrix tone-mapped look that screams HDR.
In #3, the foreground again is brighter than the sky/mountain... draws attention in a way that it shouldn't. If going for a more natural look, from the middle of the scene back to the chain and the buoy, it would be OK to allow this to be slightly darker.
In #4, this is the most natural looking exposure of the four photographs, though the hillside and foreground again are slightly too bright to look totally natural.
You've got some nice compositions to work with, and while there's nothing wrong with HDR images in this vein - if that is what you are going for - if looking to present more natural looking scenes in which the dynamic range is challenging, then as Jim suggested, I'd consider ditching Photomatrix and doing simple blends by hand.