Don't get me wrong, you have the heart in the right place - Ranked needs an equivalent to the Top 100 Feast rewards to incentivise play. In fact, Tier rewards also need something unique to them that you cannot farm in Casual, incentivising to play even outside of Top 100.

But as you already guessed yourself, you are going to get a lot of flak for saying that the rewards in question should be the previous Feast rewards. Unique Ranking rewards are essentially "Trophies" and if you re-introduce them, you kill off what makes these Trophies so sought after, you kill the "unique" of it.

I'm against FOMO as much as the next guy, but for the purpose of a Competition, you need to keep things unique, else you will have various players just return to the same question:

"Why should I play now if there is a good chance they will just reintroduce it later again for probably less effort?"
Alternatively for those who have them: "Why should I play now, I already have this?"

In short:
  • Yes, there needs to be actual rewards at the level of what The Feast offered
  • No, the rewards should be unique and not what The Feast already had