Continued! Now that we've established the basis for having the money and industry and labor force to pull off an actual return of the winged hussars, lets go step by step.
~Ground Forces~
Poland's greatest strength and potential, and easiest to upgrade.
Just get more. Begin with Hungary-style military themed summer camps. Move onto useless PE being replaced by classes that are practically mini- Hitler youth training, complete with unarmed combat and military level fitness training. Propaganda, a reinvigorated national spirit, and a pride in a blooming Poland should get you lots of fit recruits. Sort them into their best roles, while the smart stemfags go into R&D, and the weakfags go into manufacturing. Women of course go into support roles in the back lines, into the workforce, and most importantly to creating a strong stable household. Don't tax the young too hard so they can start having kids.
This is self explanatory, if it isn't you're the one who needs to do some thinking, not me.
Modernize with Pencott Wildwood, Plate carriers, better helmets, modern comms, MSBS, optics, etc. Poland currently wields a cluster fuck of personal equipment, standardize that shit with home designed home built models. They have at least one of everything Polish made to fill this.
Spam out Rosomak XP (liscence built Patria AMV XP) with Slovakian Torra 30 unmanned turrets. Strap on a few ATGMs (liscence built Kornets would be fine). Throw out the old Soviet shit, the clusterfuck of random shit, abandon acquisition programs. Borsuk IFV might finally be a thing, but unnecessary,a Rosomak APC that's uparmored to an IFV would help with production and maintenance. Recon vehicles, command, ambulances, etc should all be on the Rosomak XP type. Just keep building up a stockpile.
This is also important once we analyze Poland's armor capabilities. Squads have liscence built RPG-28/29, and platoons have Kornet ATGMs (liscenced as well for home industry).
This will be important when we analyze the Air Force. Equip each squad with PIORUNS, and each platoon (or at worst company) with Poprads. Move up to Battalion level and Noteć SPAAG should be appearing in force, as well as SRSAM Narew (if these turn out to be good, if they're shit then replace with Tunguska or Pantsyr and Tor, respectively. Brigades should see Liscence produced (or worse case scenario imported) S-400s. Fuck the Patriot batteries.
Poland doesn't have the experience designing these, but has the industry to build them. Also why would the Germans give Poland free tanks? Are they bugged? Kill switches? These are always a possibility. So Poland would have to develop something, and if not then keep upgrading their current fleet, but put more emphasis on small unit, highly mobile ATGMs. Tanks should ideally be supported by a BMPT-terminator type vehicle. Likely a Uparmored Rosomak with grenade launchers to add to its standard 30mm Torra turret.
Logistics, repair, recovery, etc etc etc. don't make me write this shit out. You get the idea. Similar vehicles and chassis for production efficiency and maintenance and smoothing logistics.