The lack of powers does not mean they can not fire a bow for instance, just that they won't be good at it. With multiclassing power swap feats they can exchange a ranger power in. So technically a Warlord with ranged effectiveness is COMPLETELY viable in game, just not as good as a Ranger with...
Just one quick note on ranged weapons, where does it say that a Warlord for instance COULDN'T use ranged weapons? Their is a big difference between being able to use ranged weapons and being good with them. If a charachter in 3ed wanted to be as good at ranged weapons as the ranger, they had to...