I think it'd be great to have buyable saddlebags for your horse, or have them just come with the horse. So you can put excess stuff in the bags for those long trips. I often have several quest locations I want to go to in the same general area, but I always have to go back to town or my house after each one to sell or drop off extra stuff that weighs me down. Being able to put some stuff in saddlebags while you're on long/extended trips would be great.

One of my favorite mods of all times in Oblivion was Maboroshi Daikon's saddlebags.
I too can't wait for someone to make one when the CK is finally out. Makes no sense
to me that my horse can't carry, anything. He should be able to carry, I'm not sure how
much exactly, but at least as much as I can I reckon. Maybe even a little more?

I too would like to see this done, I'm sure it'll be addressed by some one, I might even look into it.