Powered rails sounds great, though. Yesterday I thought about how the annoying minecart system could be improved, it's just annoying to have to feed the carts with coal all the time just to get somewhere. I thought about:
Station which automatically feeds a bypassing furnaced minecart with coal, which can store the coal in a chest.
Station which automatically stops bypassing minecarts for an amount of time the player can set. Should work so that all the carts of a train stop at the same time, and start again afterwards.