First, Khmelnisky generated a lot of troubles both to Poland and Ukraine .
Not really, he was succesfull as long as Poland was busy dealing with the big boys, Sweden and Russia.
You may call him a rebel but he managed to sell Ukraine to Russia.
Russia would have taken a chunk of Ukraine anyway, he just gave it a semblance of legality.
1654 in so called Union of Pereyeslav he did it and I think it's ridiculous that some Ukrainians consider him to be a national freedom fighter.
Well he was a freedom fighter to a degree but he was not a major threat, Pejersław legalised a move Russia would make anyway so i dont see how was his role so huge.
More, he tried for the first time in history the partition of Rzeczpospolita in Radnot 1656, together with Sweden, Prussian elector, Rakostsi and Radziwils.
He didnt try anything Swedes, Russians, Rakoczy and Radziwiłs tried, he just jumped on the bandwagon but given that Polish armies butchered Rakoczy, scattered the Swedes and expelled the Russians (Lithuanians dealt with Radziwill) he was again alone and incapable of doing anything.
The wars of the deluge period were a conflict of very big boys, Poland, Lithuania, Sweden and Russia, Chmielnicki was just a small fish trying to win what he could by the side he viewed as the most powerfull at a time, he'd join Poles after they defeated all enemies and try to play it with them, the problem was that the moment Crown would lay its hands on him he'd end up with his head on Warsaws ramparts.
As for August II, his buddy/buddy relationship with Peter I caused more harm to Poland than both Suvorov, and Muraviev Vieshatel.
August II was never a Pole, he was a king of Saxony and didnt care much for Poland but neither him nor Peter wanted to destroy Poland, if you're referring to collateral damage the country suffered, that was because of our internal weakness, kings of the time as of rule didnt give a sh*t as to what happens to the countryside, Frederick the Great burnt his own cities to the ground.
You cant really classify two guys who waged wars in Poland but not against Poland as such as our enemies.
Bismarck ... I even don't try to compare him with Hitler however he wanted to
"ausradieren" us.
So simple ... to cancel all Poles.
Naturally, much of Prussian lands were lands they stole from Poland about 100 years earlier, it was in the interests of Prussian Germans to Germinize Poles so we dont take our lands back, even today you can see BB crying about oh so German Greater Poland region we took back even though it was in Germany for only 100 years and they stole it from us in the first place.
But still he wanted to do it by germanizing Poles not sending them to gas chambers like his inheritor Adolf Hitler would and he wasnt particulary succesfull at destroying polish identity either so he's not so bad in what he tried to do and what he tried to do he sucked at.
Bandera gave the ideological background for ethnic cleanings in Volhynia.
Yes and it was horrible but on a national scale Bandera was never really a threat, at no point in its existence was pre-war Ukraine a threat to Poland simply because of the huge military and economic disparity between us.