Rump state would be strongly opposed by Prussia & Austria, so for Alex it would be better to restore 1795 borders (with RE keeping just Białystok and Tarnopol). Bonus is, that Prussia and Austria would face serious troubles with their Polish population, especially the former, which within 1795...
Well, even hereditary monarchy like Sweden under Vasas saw 2 usurpations, GDL was usurped by Kazimierz Jagiellończyk against brother's will. And Polish nobles had to swear to Mary d'Anjou before, so nothing is guaranteed.
Take it into account: oldest son and intended heir (who even may be accepted as heir by nobles of all 4 realms or already crowned) of ATL Vladislaus III died not long before him. That makes succession more chaotic and split more likely.
OTL Władysław III practically lost Lithuania and neglected Poland after he moved to Buda. Such monstrosity would either collapse or monarch would barely be in control of most of his realm, having to ceede power to local councils. Casimir IV had seriuos trouble with Lithuania after he moved to...
Having multiple sons Władysław III would want to secure their future. Poland-Lithuania-Bohemia-Hungary moloch would be ungovernable anyway-it is receipe for eternal civil war. And IOTL Sigismund of Luxembourg was meant to split the thrones of Bohemia and Hungary if he had second daughter.
And...
Hedwig d'Anjou (1374-1399) Queen of Poland, m. Vadislaus II Jogaila (ca. 1360-1434) Grand Duke of Lithuania, King of Poland
1) Vladislaus III (1399-1445) King of Poland 1434, King of Bohemia and Hungary (as Ladislaus V) 1437, m. Elizabeth of Luxembourg (1409-1442) [1]
1) Vladislaus (1427-1444)...
Obviously, losing a war against his own subject is not something, that any ruler of the time could afford, let alone Nicholas I. Older brother really left him in situation without good options with dubious gift of Polish throne. Otherwise by mid 19th century (when modern Polish nationalism...
Abstracting from chances of the uprising to succeede, if it happened it would be massive gain for Russia in the long term, as such humiliation would force RE to implement really radical reforms, which would more than balance loss of Congress Poland. At the same time increase of Russia's power...
Then Maria, Charles V's daughter, inherits Spain and Burgundian inheritance. Max II was her husband, so Low Countries are still ruled by Spanish monarch.
Sometimes Catholic clergy in newly christianized European countries supported Jewish immigration as tool to strenghten Christian faith among recently baptised pagans, making Biblical stories more credible for them: "You see? These guys from the Bible are real! So is the rest of the book"
Well, there were male Angevins around, but Louis sidelined them in favour of his daughters, with ended badly for whole Capetian House of Anjou. Had Louis recognize Charles of Durazzo as heir, things would go better for dynasty.
Bigger problem than patriots would be Russia, with whom Wettins had to deal, otherwise some patriots would be bribed and if civil war starts in PLC there would be no military force able to withstand improved Saxon army.
Hungarian Angevins: under Charles Robert and his son Louis the Great Hungary was stronger than ever, but Louis died without sons, rights of his daughters were questioned, his realm was split and Hungary descended into Civil War.