One of my favorite things to do in all RTS game is explore the map because it's usually different and you dont know what you will see or get. Whether it was AoE, Starcraft, Civilization, or anything else. CoH is the exception because the mix of gameplay and good map design always lead to dynamic battles.
With sins I don't get the satisfaction of exploration unfortunately. There is the phase lanes and gravity wells that really limits the layout and exploring. There is the exploring planets, but that doesn't feel right at the moment. I think most of the suggestions that would promote exploration have been shot down by the devs such as orbits and substitutes for phase lanes.
Right now I cannot think of any ideas to make exploring more fun, so I leave discussion open to anyone that does have ideas.