Long time lurker here as well. Here is my map along with my reasoning and premise of the scenario.
Since Germany will be unwilling to accept any form of Polish independence and is in control of core Polish territories with clear majority of Poles, of vital industrial and economic worth, conflict with this state will be inevitable. Russia has territories with low number of Poles, mostly dispersed among Ukrainians and Belarussians, with only a few centres of Polish majority, and proved that it is willing to accept loss of core Polish territories like Warsaw, unlike Germany which engaged in settlement and colonization of areas like Poznan.
Thus Poland must focus on securing its position versus Germany, while trying to forge good or neutral relation with Russia and alliance with Czechs.
My premise assumes non-Pilsudski Poland, oriented west, with alliance with Czechs, and intervention in Russian war on the side of Whites, result of which is either a stable monarchic regime with military and trade alliance with Poland or more warlord torn nations but still neutral towards Polish territories.
Leave Lithuania and Belarus alone-lack of vital resources, and puppet Lithuania using local minority that will form 30-40% of population anyway and dominate politics making it a duel nation state.
Poland is led by nationalist instead of Pilsudski faction, who focus on good relations with Russia, France, Czechoslovakia, Italy and Yugoslavia.
12-14
oland must secure access to the sea for its trade with Western world. Having Gdansk saves tonnes of money that were used in OTL for building Gdynia. These resources can be used instead for industrial development of Polish territories and expanding military production.
37:Lviv is an important economic region, with vital university and Polish majority, securing it would be a green boon to Polish state, but it is not top priority.
4,5,6: Poles form majority in Upper Silesia and the region is lifeblood of Polish independence as it houses necessary mineral resources and industry.
23,24
olish majority, needed to cordon off East Prussia from Lithuania and vice versa
17:Would be ideal to take immediately, as it has strong Polish minority and German exodus would probably reduce German presence, needed to make Polish border safe. However it is likely that it will be only possible after next war started by Germany.
I marked Southern expansions, indicating neccessary alliance with Czechoslovakia, Romania and Yugoslavia against German clams and revisions of Versailles Treaty.
Further German expansion is marked due to fact of inevitable conflict with German state, which Poland must win by securing needed alliances. Some territorial changes would have to be made then.