How can they add more classes and make them unique and have their own flavor?

[Shurrikhan]

How?

Honestly, by not being so stingy about putting in truly new mechanics, and by building the job as they feel it should be first, and balancing it after. Identity, fun, and balance, in that order. Well, the first two interchangeably, I suppose. Whatever feels like the job, in a fun way. Then finally balance.

Mechanically-speaking all we got with 3.0 were literally proc guarantee, RNG combo-finishers, RNG buffs, sacrifice-able RNG buffs, buffable RNG buffs, duration-consuming abilities, and a player-created doom state. That's mechanically all it had to offer. Which is why I have to assume a quizzical face briefly when people call DRK and MCH "different" from their lineup. They have their differences, and after mastery may come to feel very different, but on paper (and almost certainly in code) they are really quite similar to their precedent jobs... and the same, precedent design philosophy that would rather copy-paste their way to parity than focus on balancing after having fully developed more original identities. It's also why I can't understand why the coding of all things would be an issue, despite that being the alleged reason tossed about on these forums. The art resources seem costly enough, or perhaps even the (often none too well received) job quests, but to say that the coding itself would take up that much time, when almost every bit of it already exists in game... I can't really fathom the idea.