Thanks for stating this. I think the discussion has evolved a bit as it became appearant that a node keeps getting vetted despite being full however only if he has data from the corresponding satellite. If a satellite cannot put data on a node because it is full then no vetting can take place for this satellite.
So in continuation of my initial question, I think there should be ways to prevent blocking of vetting due to capacity some how, maybe like my suggestion here: Test Data on the Storj Network and Surge Payouts for Storage Node Operators