I am at least 165 hours into Skyrim. I don't have a horse. Don't want one. Why? Because of the stupidity of not being able to defend yourself while mounted! By the time that you dismount and draw your weapon, whatever is attacking you has just taken half your health while you were doing that. So, I don't bother with horses. It was the same problem in Oblivion.....and Morrowind, as I recall.
I also dislike that it is restrictive if you want to dismount & fight. If i have an Alchemy based character it's even more restrictive.
Overall i dont mind them, i just use them occasionly, no rule says you have to use them.
In Skyrim, once you mount up you're forced into 3rd person. I would assume that forced 3rd person view would be for the purpose of showcasing some excellent animations or visuals. But in Skyrim, 3rd person view means that for some bizarre reason, your mouse changes your direction, not your view. So instead of being able to look up at the towering mountain vistas, I'm basically stuck looking at my horse's rear end while I'm riding. Great!
If i want to check out the scenery i use the WASD keys, hold down W then use the mouse i think it is, or A or D.