Sun badges are epic. Earning them is a true challenge, and they require impressive dedication. 

Here is some ideas for new sun badges! I also suggest bringing back the retired ones.

Currie: Achieve mastery in 750 unique skills.

Hawking: Achieve mastery in 1000 unique skills.

Thrice the Millionaire: Earn 3,000,000 energy points NOTE: If the KA team brings back the Ramanujan badge (Earn 2,000,000 energy points), then this might not be the most needed. If not, this might be a suggestion.

Fifth Times the Charm:; Earn 5,000,000 energy points NOTE: I believve this is the most important one, because from Tesla (Earn 10,000,000 energy points) to Millionaire (Earn 1,000,0000 energy points) there is a vast expanse, and there needs to be an in-between badge. P.S. Please bring back Millionaire. Although most has haad it, there are still some that didn't.

Salmon Khan: Earn 7,500,000 energy points NOTE: It can also be 7,000,000

And that's it! I hope also, that streaks are going to be back. Also, video badges can be  considered for watching 10, 25, 50, 100 and so on videos. Thanks, and hope you'll have a nice day!