I cant speak for myself, because I did it before golden pearls were available from mirror lake. Before mirror lake, those golden pearls. Nightmares. I spent hours a day just to get one. If even one that is. Now for anyone almost with mirror lake unlocked, it isnt to much trouble. Even so, people sell the golden pearls they get at the bazaar. For the sunstone, farm bosses, or farm stone town for the sandstone harvest. For aether, if you wait a few minutes, you can usually get 2-3 aether. Those are the main difficulties.
Other than that, on a scale of 1-10, (difficulty) I would give it a 5. Spirit caller drums are the thing that will scare you. lol
Yeah, don't forget the transmute option, it makes many of the needed reagents much easier to obtain; especially compared to when the seal of seven seas was first released when CL debuted, no harvests of sandstone or chance of sunstone, had to transmute it all from stone blocks. Ah the crafting memories...
What a funny name the quest name has but how hard is it to craft the seal of the seven seas?
For me the Seal was where I drew the line in crafting, I do it on only one wizard on each account because I craft the Wintertusk gear and do not do WaterWorks. I like crafting up until Celestia so after that it becomes a mind game - do you really mind spending hours to collect this stuff?
Other wise I don't garden for what it can drop or farm for anything so really that puts crafting out of my idea of fun in the game.