If that was the case, then those test/development drivers would not be test/development drivers but actual race drivers.
Neither Perez or Hulkenberg are 'paydrivers' though offcourse Perez does bring a wealthy sponsorship deal through Carlos Slim,
but almost all drivers have some form of 'sponsorship' accompanying them that brings a benefit to the particular team.
You could actually say that for someone like Hamilton too. Offcourse he is a good enough driver to actually be able to home in WCC's and WDC's,
but if you would reason that the Merc Wxx F1 car is fast enough anyway to home in the WCC and atleast one of them the WDC, then you are obviously
rather 'free' in driver choise.
Fact is, Hamilton is a very popular 'brand', and having someone like that aboard brings a investment return that is absolutely worth it.
Now to go back to a team like Force India, you might argue that 'Perez' is not a guaranteed top+ driver like Hamilton,Alonso, etc. [ though it would be interesting to see what
he can do in a front-running car ]. But he brings with Slim sponsorship money what Hamilton does by having become a 'brand'.
The interesting side of it all is that if Perez actually would get a real competetive car like the Mercedes or the RedBull, and he really turns out to be a driver capable or in the
caliber of Hamilton himself, Rosberg, Raikkonen, or Vettel for example - in other words ; he gets that car in P1 or P2 just as good as his teammate does - then Perez, in the end,
might even be a bigger interest for teams because he is
a) brandable -> Lewis wasn't the 'Walking moneymaking celebrity' he is today back during his debut in 2007, after all, so why couldn't Perez become a Celeb playboy?
b) sponsorship connection -> Perez is directly linked to Carlos Slim, so he can bring in TelMex money, which is capable and in the right circumstances surely willing to throw
so much money to the team that no other sponsor alone is remotely close to achieve.
for example; let's say Carlos Slim is WILLING to slam in 100 million EUR for each season, if Ferrari hires him and gives him a championship-winning car.
Ferrari themselves already have for example 150 million in own money to throw at it, and then they have their own sponsors like UPS, Shell, Marlboro to burn, lets say that
equals another 250 million. offcourse that 400 million gets spend with or without Sergio, true. But then Sergio also brought in a mexican oil sponsor to Force India despite
Force India running a Mercedes engine of which im 100% sure isn't running on that mexican oil. Lets say this is worth about 15 million eur.
Then imagine Perez' paycheck comes in the form of 1 million EUR - hypothetically.
So, Perez brings a team through direct income:
115 Million EUR minus 1 million salary equals 114 million USD, AND is capable to be a WDC.
Now Hamilton offcourse brings in a vast amount of potential and experience, where Perez simply isn't at yet. So that might speak for Hamilton over Perez.
But then, years of topdrivers still haven't brought the wanted results. So Ferrari might be open to something 'different' than just simply 'a topdriver'.
A combination of Hamilton - Alonso would sound great, but if the driver isn't neccesarily the reason they're not getting the results they need, then i repeat,
they could reason they must be open to something 'different'.
Now money speaks, and let's say Ferrari would have 400 million USD to burn. let's say Lewis and Alonso would cost 50 million each. that's 300 million left to
spend for the car.
Another option - something different - would be for example; Perez - Button.
Let's say Perez wants 1 million, and Button wants 2 million.
Suddenly, Ferrari has only spend 3 million and thus has 397 million EUR to spend on the car, that's a whopping 97 million MORE than with Lewis and Alonso aboard.
That's not all, as Perez brings in 115 million just by being there through sponsorship deals.
So that makes a total of 512 million EUR all of a sudden to burn. That's 212 MILLION EURmore.
Knowing neither Alonso, neither Raikkonen, neither Massa, neither Vettel have given them the WCC they are looking for - hell, they're not even winning now - one
could argue the 'rule' to have such a capacity driver could for a change be 'overlooked' in favor of someone like Perez and Button [ remember, Button is a WDC after all
and superbly experienced ].
So Ferrari has 212 Million EUR to burn into technical and team structure by hiring Perez-Button instead Hamilton-Alonso [ example] .
Now, Newey offcourse is rather busy with Aston Martin and RedBull, but no doubt Ferrari is hot to hire his services. Let's imagine Ferrari offering Newey 100
million EUR for each season, and a couple million extra when he gives them a WCC winning car.
Ferrari STILL would have 112 million EUR to burn in technical and personnel/team structure;
Strategy, pit crew, etc. Let's say they decide to spend 3 million to buy the entire williams pitcrew and it's pitcrew 'head' for a year of their services. let's say that's a
crew of 12, that means about what, 250.000 EUR each. I wouldn't hesitate for a second if i was asked. I dont believe for a second williams is paying anything near
that money. So 109 million left to burn. half a million for a good strategist, another half million for somebody better qualified in tires and you still have 108 million to burn.
I think spending 54 million on the engine [incl. gearbox, ers etc] EXTRA and 54 million on the car's body, aero and suspension EXTRA is still a conciderable benefit, especially
remembering that they had about 400 million EUR to spend on their car either way, this is all extra to 'gain from' compared to hiring Alonso and Hamilton instead of Perez and Button.
Personally, I don't think Hamilton and Alonso weigh up that much that they would 'nihilize' ALL that money. Remember, 212 million EUR LESS to spend, no Newey aboard, no Williams
pitcrew, etc.
Don't get me wrong i concider Alonso and Hamilton better than Perez and Button, but evidence is that assumed better drivers than both Perez and Button in the form of Vettel, Raikkonen, Alonso and Massa have NOT brought in results.
Long story short;
Perez definately has potential to end up at Ferrari. The big question is why they decided to go on with Raikkonen for another year. I rather think this is primarily based upon what they have already 'developed' for the 2017 year and the big rule changes surely would have them concider Raikkonen more than would have been the case had the rules been the same as this year.
They also have another year to see how Perez pans out to be after the rule changes.