Including new member states to ensure further cohesion in wider Europe, while at the same time continuing to address inequality, racism, and nationalism are the pathways that should be followed for the EU to avoid less desirable scenarios.
For many years Poland has been a part of the community in which there are no internal matters of a given state. Even when talking about exclusive competences of member states (eg. the protection and improvement of human health, indusry, cuture, tourism, etc.) these still are a part of the EU law.