lot of players hunt collections, some collectible items can be only from legend rank so need lot of packs till cap
They "need" to, eh? Again, there is no one forcing them to fill this "need."
have goals to the game is very healthy, but EA make it unhealthy so far with random luck
All games involve random luck to one extent or another. Again, it someone doesn't like the way it works, they are free to not participate. There is nothing in the CM that is essential for questing in the game.
and lot of credits and the BOP system
Most items from packs are not
BoP. I'd like it, too, if the Cartel rep items were not BoP, but they are, so that's the way it is.