You weren't talking about top teams though. You said lesser teams. So we are saying instead of Kvyat/Gasly, Stroll/Perez, Riccardo/Ocon, Grosjean/Magnusen you'd get Gasly/Yamamoto, Stroll/Canamasas, Riccardo/Phillipe Adams , Grosjean/Trump.
The number one number two thing is a completely different issue and exists because it's a team sport. Big teams would not take a pay driver on as their second driver because they wouldn't want to risk the teams championships, so they employ the best of the second tier. The smaller teams would take the gamble on one driver as they are not in the running anyways.