Silvermoon and Exodar are so far out of the way and in their own instances, on top of that Darnassus and Undercity are better, more populated faction hubs to hearth to, it's not worth going back to either Silvermoon or Exodar once you have the faction bags. I don't get why people complain about Gnomeregan not being re-taken yet (not that anyone has in this thread). It's unnecessary to have another capital city when Ironforge is literally a minute away. You only need so many faction hubs for low level questing.
Just wrapped up Shadowmoon Valley's quest chain, I thought the end of Frostfire Ridge was epic, but the battle for the temple was on a whole other level. There's actually more lore to the Iron Horde in the Alliance starter zone than there is in the Horde one.