good idea, but does not apply, for champion gear you can just grind out bags in WZ's while you gain valor, after you are valor 60 you can open new bags for BM gear, which you can get a max of 2 a day and 4 on tuesday, not awhole lot of chances if RNG hates you.
What they need to add in is a champion-BM token trade in, i'd be fine even if it was a 10-1 ratio cause at least I know i'm going to get the gear at some point.