Honestly, I wouldn't say Power Launchers suck because you can get more damage out of a PL combo than a Power Blow.
The problem is the risk that a Power Launcher brings along. Even when doing a no-timing Power Launcher combo there is a chance that you make an input error, mess up your combo and the damage can not be dealt anymore. At least with a Power Blow you have guaranteed damage, and sometimes you can aim the camera in such a way to slam your opponent into a Power Blow exclusive dangerzone. If the latter is the case, a Power Blow could result in even more damage than a Power Launcher combo.
That however, does not render Power Launcher combos useless. It also does not take away the style points you get from doing a successful PL combo. From my point of view, I favor Power Blows, but Power Launchers are definitely NOT useless.
This is why I voted for the third option.