On Exile Erebus can use his jump ability or whatever it is to jump into the enemy spawn from the outside loop and mist in it indefinitely, giving sight to any sniper regulus on his team picking off half dead demigods coming to heal at the crystal, or finishing them off himself. I think he can also plant the sight totems inside the enemy spawn so that sniper regulus can have a lot of harrassing fun.
That's a minor flaw. Now for the major flaw:
The map design on Exile promotes stalemates. Even if one team seizes the last flag and has Giants pushing, the corridor is too narrow and the distance to the health crystal so close that they can hold off anyone indefinitely until they get giants of their own and promote the stalemate even further. I've played multiple stalemates on Exile, and while I have become somewhat of a Stalemate buster, I think the map should be redesigned to stop stalemates from happening as all they do is delay the inevitable for an hour (if I've capped all their flags and pushed into their spawn til the health crystal, chances are I'm going to win, the only question is how long it will take).
To fix both these problems I recommend positioning the health crystal onto the opposite side of the spawn on exile than where it currently is, or in between the two portals somehow. I also recommend that the portals have flags.
That's all.
-rendari