The first mode anyone goes through should be easy (or story) mode. That way the dev's don't end up making important storyline content that only the upper 10% could see. I say that as a former hardcore player back in ffxi who was on the bleeding edge of content. CoP was the most amazing storyline SE has come up with in the past few years, partly due to the difficulty. Although personally, I'd lower the "difficulty" a bit by opening up the content to all as far as jobs/classes (as opposed to "x3 blm, x1 whm, x1 brd or rdm, x1 tank). Having fights be tough due to coordination and timing is great. Having fights be tough since you're not bringing in a minimum of 4 faceroll classes is not real difficulty.

I'd ideally like to see something along the lines of SWTOR's tiers:

Story Mode (intro raid level, fairly weak drops but full storyline)
Normal Mode (Where the "real" game begins. Powerful drops, upped mob damage and health, new boss abilities)
Hard Mode (Upped damage and health from boss, new abilities, shorten acceptable margin of player error. Best quality drops in addition to possible optional bosses)