Bridging the renewal gap

What are the least painful ways to bridge the gap between two renewals of the GV, as far as Schengen travel is concerned, if you have a passport which doesn’t allow automatic visa-free travel to the Schengen zone?

Especially given the long and uncertain durations for biometrics, and the possible resurgence of Covid? Tourist Schengen visas would have been the way out in normal times, but in Covid times they are simply not issued or honoured, while residence visas might still be able to get you in.

I understand one would be street legal if resident in Portugal during the renewal period, on the strength of having an application pending with SEF. IIRC they had even modified the ARI portal to issue a certificate with a QR code which you could show anyone like potential landlords to confirm legal residence status. But do these kind of SEF papers allow you to

  1. Travel within the Schengen zone?
  2. Exit and re-enter the Schengen zone? Somehow I don’t see airlines taking kindly to me waving an expired residence card and a paper with a QR code.

Short of applying for another (expensive) GV like the Greek GV, what are the least painful options? Thanks!