EC representatives criticized member states that closed their borders first (especially central and eastern members) but now it appears that these countries will be the first that would be ready to open the borders again (at least for visitors from countries with low infection rate) because they managed to keep the epidemic at reasonable levels.
It is now very important task for EU central institutions to coordinate the measures of the “smart quarantine”, in particular the electronic contact tracing so that it would be possible to trace the infection spreading across the open borders which is essential condition for opening the borders. There has been an initiative of European academic and technological organizations called PEPP-PT (Pan-European Privacy Preserving Proximity Tracing), yet most countries have developed their own variants handled by their own national healthcare authorities which of course does not help in case of open borders. Moreover, Apple and Google have just issued a new API just for the contact tracing.
That’s why I think it is a mistake to make EU focus primarily on money - money itself cannot do anything. EU should rather focus on coordinating just those tasks that are important to be (either centralized or coordinated) across EU in order to restore cross-border activities within EU. And proximity tracing is a very important one!