alternatehistory.com

Henry III, Duke of Głogów, was one of main rivals of Władysław Łokietek in struggle for Polish Crown. Although he wasn't as lucky (Łokietek's career 'from zero to hero' was one of the most ASBish events in Polish history) and longevity. Henry controlled his native Duchy of Głogów and most of Greater Poland at the time of his death in 1309, but his young sons quickly ruined achievements of father and were driven out of Greater Poland by Łokietek.
Say that Henry is the one with Łokietek's level luck. Thus:
-Łokietek dies earlier (perhaps during his escape from Cracow) before death of Przemysł II. Przemysł's lands (Greater Poland and Pomerelia) were disputed between Łokietek (married to Przemysł's cousin) and Henry of Głogów (who was Przemysł's cousin and designed heir before Łokietek married Hedwig of Greater Poland). With Łokietek being dead Henry would be most likely heir of Przemysł.
-Wenceslas II of Bohemia also dies earlier (say his health deterioriates faster and he dies around 1300). Bohemia has now underaged monarch, Henry has opportunity to grab Lesser Poland.

With these conditions fulfilled Henry should be able to get Royal Crown (and would rule as Henryk III-he regarded himself as only rightful heir of his great ancestors-Henry the Bearded and Henry the Pious) before his death in 1309 (without episode of Wenceslaus on Polish throne it would be less problematic-Czech King would not have claim to the title, although would still have claim to Lesser Poland). That would secure Henry's realm from disintegrating again.
Poland, not being torn apart between two claimants like IOTL would not lost Pomerelia in 1308. In addition Reunited Kingdom of Poland would include large part of Silesia (with perspective of getting more-Upper Silesia is insanely fragmented, Henry VI last Duke of Wrocław died in 1334 without sons, he was conflicted with brother and allied with Piasts of Głogów against him, one of his daughters married son of Henry III of Głogów, also his duchy was divided from Bohemia by Duchy of Świdnica and Jawor, thus Piasts of Głogów are the most likely candidates to swallow Duchy of Wrocław).
Thus reunited Poland under House of Głogów would be bigger and more stabble, and Silesian-centered. Silesia was richest and most populous part of Poland, Łokietek's Kingdom without Silesia and Pomerelia was in fact rump state) and would not be conflicted with (weaker ITTL) Teutonic Order, which would likely one day became Polish vassal. Lithuania OTOH would be main rival and fileld of expansion of Kingdom of Poland.
@krieger
Top