Now that I have more time, let me explain...
I recently did Poland in a week, we were very rushed to cover ground, and yet I feel like we still didn't cover it all.
You can add to a trip like mine Kerestrir/Budepest which is half the distance as Berlin from Krakow. Prague AFAIK will need more than just a day or 2.
Warsaw is a day or 2 of what to do.
Lublin is easy another day.
And Krakow is a 2 or more days with Auschwitz/Auschwitz-birkenau.
That right there is a week without shabbos, and than there is all the other places on the way such as;
Przeworsk (Pshivorsk, Not sure what's still there)
Dynov
Warka (Vorka)
Ger
Kozienicki (Koshnitz)
Kazimierz (Koshmier)
Shinov
Ropshitz
Riminov
Majdenak
And a whole lot more.
The list goes on and on, not sure how much kvarim you intend to visit, but even the basics, with the other attractions, such as Museums, Ancient Shuls etc. is plenty for a week in Poland alone, especially if you're not a small group. Also remember the weather there is bitter in the winter.