Just to be a stickler, Abby is pacing 40 points in an 82 game season with his missed games.I'll take the 40 point player who is physical and pretty sound defensively.
Helm is no longer notably fast and as you point out has hands of stone. Replacing a guy who's a good penalty killer and good defensively (hello Glendening) is a lot easier than replacing what Abby does. Abdelkader is on pace to put up 37 points on this craptacular (and now full on tanking) team. He's been one of the bright spots.
Don't get me wrong though, I hate both their contracts.
Give me Abby 10/10 as a hockey player, the term is just awful.