Well I will stick with this era since most finishers from the past, mostly from the Hogan era are taken as weak but at the time they were pretty impresive.
Like most I most said The Play Maker looks weaker than most, There is a reason why Randy dropped that Finisher so many years ago.
The Attitude Adjustment, Is not a DVD and Cena protects his victim too much, I mean he almost birng a cushion so his victim can fall with no harm, not even the one over the top turnbuckle seems that hard.
The Styles Clash: AJ is great and all but that one seems weak, really weak, is like half a Dominator and AJ is not a big guy so it seems rather weak, I don't even buy it When Michelle McCool applies it to another Diva, She was better of with th Angel Wings, then again that one was too much for the Divas.
Now defending some moves.
Talking of the 619, it is actually a set up move (I know, sucha long set up for a nother set up is crazy) for a slpash or something else.
The Hell's Gate move, first is a submission move that can choke out any one, Really difficult to pull out on MMA but if someone locks it up, the victim passes out in a matter of seconds.
The KillSwitch: I mean is obvious it can be countered very easily but even if the set up is difficult, The move is not weak at all, on the contrary, there is no way it does not Knock you out since is supposed to prevent any protection to the head, and Christian makes it look good most of the time.
The RKO: someone said that Randy only uses one set up for it, that is not true, the guy can practically pull it out from a lot of positions, He chas countered tons of moves and hit it out of nowhere, he countered a choke slam, a top rope tackle, a Crossface to win his first World Championship and the Pedigree with it.
Edge's Spear: Yeah sometimes it seems like a hard move but not one that will put a Big man down for the count, specially since Edge does it from his left side and not like someone like Goldberg who used a tackle right at the center of the opponent but truth be told Edge can set it up from a lot of positions, as a counter from a top rope move, as a top rope move, counter of another spear like he did with Batista, etc.