Right now, when someone is raised, he likely has no idea where the healer, and when he accepts it, he'd be tractored to the location of the healer where he would be raised.
The problem, apart from being vulnerable (which I personally find ok), is the possibility of a detrimental ground effect/an enemy aoe that is being cast to be exactly where such a person is raised, and right now, there is absolutely no way for the raise-ee to avoid it.