I went in-game and checked the journey menus. So lets see:
We have 83 days left on this first 'Journey' (Btw, is this a lowkey leek of when the 1st expansion of 2020 will release?)
There are 100 levels on the journey, each requiring 24 crowns to level up (24 rounds won)
This means even if you do level up once a day, which should take on average two hours per day, EVERY DAY for the next 83 days, you will still only reach Lv 84 and not unlock all of the rewards, and some of the best are in the end!
This is some BS. And the free rewards are really bad, only avatars, you could at least give some animated border/ coin on milestones like lv 25/50/75/100...