Wrocław is a useful start for Lower Silesia. Check seasonal conditions before adding a mountain accommodation base.
The airport says rental desks are in front of the baggage-claim zone and rental cars use a dedicated car park at the terminal. Confirm the booked firm and vehicle-return space.
A car is useful for rural accommodation, lake districts and a route with stops beyond the main rail corridors. Warsaw, Kraków, Gdańsk and Wrocław city stays can be separated from the driving days to avoid paying for unused parking.
Compare airport collection with a later collection if you start with a city stay. Include the transport to a different rental branch and any extra parking nights when comparing the total cost.