Options for mid lane mages

I have been hearing some friends of mine who play mid mages complain that there is no good early item against ad mid laners. They say if they buy mana they don't have armor and die and if they buy armor then they run out of mana and die. Now the pros have the skills to work around this or perhaps deep enough champion pools but for regular shmos it seems unbalanced. Is this intended? I was thinking that Athene's could have two build paths. One as is and one that builds out of armor instead. That way there is no need to make a whole new item. Thoughts?