Perez will be more than happy with his lot imo. The amount of teams that can actually win races on genuine pace is staggeringly small now and in the past.
He had to wait 190 races before his first win which was a freak win due to a number of factors luckily going his way (plus an incredible drive).
So if you've got a choice on whether you want to be the top dog in a midfield team or a number 2 driver who can still win races when the opportunity arises then for me he's in the best seat available.
Sure Red Bull do favour Max but they'd be crazy not to. If you look at the drivers on the grid Verstappen is one of, if not the fastest driver and he's still young.
Hamilton and Alonso are past their peaks and soon to retire. Leclerc hasn't quite materialised into the world beater I thought he would with too many errors. Sainz is another Perez i.e very good but not great. Then the rest such as Russell, Norris, Ocon etc are unproven at the very sharp end.
The Red Bull core trio of Horner, Verstappen and Newey is world beating and I'm sure they're eager to keep them together for as long as possible.