well yes you can anticipate but still the time it takes , min 8h ,is to dam high for a daily rankings .
That is the biggest issue atm top 3 ranking gets harder and harder , with each passing day , then impossible (without $ packs) once you finish the 70 quests as you said.
So the game just keeps putting payblocks one after another in an event that should be free to compete and complete with a decent amount of work for everyone and easy(very) for those who pay. It is rly not good business model at least in the long run.