Lovely views and beautiful skyscapes ... you DO live in a beautiful country (don't I know it!?!?) and you had some wonderful sunrises ... and you are ever so lucky to have the chance to see them while looking across the sea! Makes sunrises/sky pics ever so much more interesting.
But the critique of the centred horizon is, of course, right: photos - especially landscapes of this kind - do become more interesting when you (first of all) follow this famous Rule of Thirds and place the horizon either on the (virtual) line that would separate the UPPER third of your frame from the middle one, or on the line that would separate your LOWER third of your frame from the middle one.
It depends on what you want to express: is it the majesty of the sky and its vastness and drama then give the sky more room within your frame. Is it the expanse of countryside/water that you mean to show more, then give the country/water more room.
In your photos, with the reflections and parts of beach etc. it would have made sense to give the land/waterscapes some more room, though SOME could formations (as in 1) suggest you might have wanted to focus (as in "concentrate in") more on the sky than on the land/water.
See what I mean?