Genestealeralpha, do you frequent the GW store in Harvard Square Massachusetts?
Well, having that huge point sink, makes up its points regardless of what happens, if they die, they soaked up fire, if he hurts anything with guns/cc it's a bonus.
For people who are unprepared they will not know what to do with the squad. That unit can still affect experienced players, do they want to deal with the squad or do something else.
It's an interesting unit, instead of just another All genestealer army, all swarm, Godzilla list tyranids.
If we are talking about points efficiency, cheaper is always better, (more points into your army). IMO, either HQ's are dependent on your army or your army dictates your HQ. So, if you play a cheap flyrant, there should be other 'fast' elements to the army. Usually, Tyranids are so good in cc, for efficiency, why not orient them to cc. Shooting is useful, but fluff-wise too, tyranids like to munch ppl face to face.