It's a hard call, because some drivers have only been driving for less than a full season, others have spent their entire F1 career in mediocre or back-marking cars.
My best guess ("+" means he could be moved up, "-" means could go down):
Class A - Most able to win a WDC
1. Hamilton (almost there)
2. Massa (almost there)
3. Kubica (let down by car) -
4. Alonso (proven)
5. Raikonnen (proven) -
Class B - Possible WDC but unproven/unlucky
6. Vettel (fast but unproven) +
7. Trulli (fast but bad cars)
8. Webber (fast but bad cars)
9. Rosberg (bad car) +
10. Kovalainen (fast but unproven) +
Class C - May win some GPs but not the WDC
11. Glock (mediocre pace) +
12. Piquet (too many mistakes) +
13. Heidfeld (struggles too much with setup) +
14. Fisichella (consistent but too slow)
15. Sutil (fast but inconsistent)
16. Bourdais (consistent but too slow) -
Class D - Unlikely to win any/more GPs
17. Button (one 1 GP win in 8 full seasons) +
18. Barrichello (way past his prime)
19. Coulthard (retirement mode)
20. Nakajima (inconsistent and mediocre pace) +
Well Button seems to be more intrested in the poltics then the racing and Barrichello has had a fair share of luck this season, and isn't really that quick.
Imo Nakajima is very underated, no one realises that he is staying with Rosbergs pace in nearly every race(It's hes first full season too).
I agree that Nakajima is under-rated. However, I think the only reason why he's kept up with Rosberg is because the Williams is a worse car than both drivers. Both appear capable of out-driving their machinery, so their performance is more a reflection of the limitations of their cars, than limitations of the drivers themselves.
Same situation at Honda.
Flip the situation over to McLaren: their cars are equal or better than the drivers, so the discrepancy between the drivers is stronger.
It's obvious when you watch his style even in a car as shit as Honda's. He surges forward in the wet whenever he doesn't get the short end in a first lap crash or other such nonsense. He's one of the smoothest, most clinical drivers on the grid. That isn't necessarily always the fastest though, in this modern of age of huge downforce and critical tire temperatures requiring a more aggressive style than his. He has a similar problem to Kimi in the Ferrari. I'm not saying Button's the best overall driver on the grid (that's why I put him in #2,) but to deny his talent is daft.
Rosberg out-qualified him by 9 places and out-raced him by 6.
Huge downforce and critical tyre temperatures don't necessarily require aggressive driving styles. Kimi is fantastically fast even with his very balanced style, as long as the car is set up to his liking.
Modern F1's narrow tolerances require creativity, and adaptable driving skills to match that creativity. As the driving environment moves in and out of the optimum performance envelope of a car in a given setup, drivers need to adjust their method. Lewis, Kovi, and Kubica do it reasonably well given their lack of experience. Alonso is very gifted at it, and Trulli does it well too. Massa is terrible at it.
For some reason, drivers with reputedly ultra-smooth driving styles don't seem to be able to adjust their style to changing conditions as much as the more unorthodox drivers. Kimi and Button have supreme driving technique - very much textbook style - smooth steering, braking in good time, changing gears before committing to a corner, throttle-balance mid-corner, smooth power-up on exit, etc. It makes them perform well in the wet, because smooth styles make vehicle handling more predictable and consistent; finding and keeping the limit is simpler when driving smoothly. But emphasis on smoothness is a one-size-fits-all solution to high-performance driving. There are times when you need to step off the textbook and do something funky to get another extra 1 or 2 percent from the machine (take a look at rally drivers for extreme examples), but neither Button or Kimi seem able to do that as much as some other drivers.
Just because she is fast under the rain? Well she is not the worse of the grid, that´s sure, but a goog F1 driver should me more complete, not just goog in wet.
Well she is not the worse of the grid, that´s sure, but a goog F1 driver should me more complete, not just goog in wet.