Welcome to the forum - always nice to have another member of the Great White North clan on board.
Nice images - which lake? The only nit I have is that #3 looks a little oversaturated - I have seen prairie sunsets and I'm not sure I have ever seen that shade of blue, but could be that you are farther north than I am and maybe that makes a difference - don't know. These are the kind of images that just scream for a graduated neutral density filter...

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The curvature of the horizon in the third one maybe related to the focal length you took the image at - which part of the 18-105 did you use for each image?
The only thing I would do, is either place the sun right in the middle of the picture (yes it does violate the rule of thirds, but is permitted!) and place the horizon along the lower "thirds" line -this emphasizes the sky, which is what I presume you want to do here.
Of the three, I like the first one the best - has a good foreground anchor and the birds add some interest to the middle ground. In the second and third images, there is no foreground to provide the perception of visual depth, so we are left to wonder about scale, but that is not necessarily a bad thing. HTH.
Cheers,
WesternGuy