If you want really big numbers, Monk is sadly not where you want to look. Dragoon, Black Mage, or even Bard and Machinist have the potential to output really big singular numbers.

Also don't worry about perceptions of the classes to be honest. Square generally does a good job keeping them really balanced, and in practice a lot of the differences actually even out to them providing fairly close ranges; so play the style you personally enjoy the most.