Cruicible stuff

So, about the echoes of crucible, is it just me or every time im picking echoes and i start getting that rogue-like build i wanted to get, the game says: nuh uh now you only get random echoes enjoy. Is there a purpose to this? or are you not supposed to get that many echoes?
Maybe make it so that getting random echoes is a option not necessity?
Also can there be a higher numbery variety so that you are not always getting lets say 10% more dmg echo, but make it so every dmg echo has a range: lets say 5-15% dmg. So that way it feels much more rewarding in a run where you get that top number.
Thoughts?