Really nice man. Love how you are playing with the details now. I see you are open to what to do with the foreground. I like what you have my self, but here are two image I found that you may be able to make use of. Kinda a blend of the ideas from your 1st image, and your last image.
In both cases you can still have water, still have ice, and still have those beautiful reflections, while also having more visual interest in the foreground like you tried in your first image.
Having already seen this, and because I am greedy to see even more TG renders, I would be happy to see even more changes like in my example image. But I am not saying make the lake into a river exactly. The thing I like most about the example images are the Marshes, which are common in Iceland, and would help to make your render even more of an Icelandic image. As it is now (last image), apart from this contest, if you told me that the scene was of the Arctic, I would believe that too. Adding in the marches and some still green moss with some winter moss, would help to define the image more as Icelandic, for me. But allow you to keep those refections to a more subtle level.
Just my thoughts. But again, I like what you already have now, a lot. So... Cheers