Poland really can into space. However, the start can be a bit tricky. So here's a guide for newer players with recommended expansion strategies, how to deal with Polish events and my own quick playthrough till 1617. Hope it helps!
How to Dismantle HRE - https://youtu.be/OkbWVmpWdQ8
How to Convert Religions - https://youtu.be/Gb7CxztH2MQ
Text guides - www.eu4guides.com
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