The first series of photo's all have a nice mood of colours to it.
But if there aren't a lot of clouds or something to fill up the sky I would raise the horizon to 2/3 of the photo.
Your second serie makes up for that the sky is more interesting.
Like said before straighten the horizon.
Get something interesting in your photo could be building, an object...
I must say the last one of the 2nd serie is really goo imo.
Nice reflection, if you have a spot like that stick to it and wait until the sun is really gone. Take every few minutes a photo.
If the sun would be lower it would maybe be even better...