Well I'd say I partially agree with you on Button. Look at last year, aside from Sebastians dominance, who was the clear #2? Button. I think with McLaren more built around him, he has a chance at a 2nd title before he retires. I think that there are three drivers that stand out.
Alonso-Simply I think the best driver, not far above Vettel, but he does amazing things with a car that isnt the best. Vettel-Has a great combination of team, car, driver, that is why he is dominant, however I think it is also important to remember that he is close to the level of Alonso, at only age 25.
Hamilton-Personally, I think the most talented, fast driver, BUT he has too many personal issues and isnt focused enough to be a championship contender every year. Every drivers mentality is "winning, winning, winning" his seems more like "winning, personal life, looking cool, money, etc." and that just doesn't cut it to be the best.
Also Kimi and Button are quite elite drivers not far behind these three, then Kubica, who is like Hamilton in how talented he is, however who knows if he will return to an F1 car.