I think some videos watched badges are great.

Khan Academy already had some video watched badges, but they removed some of them about 2 years ago.

You can still earn these too though!

I mean, can we get badges for like, watching 100 videos, 300, 500?

No, not yet at least.

I gave some ideas to the KA team on these two articles: https://support.khanacademy.org/hc/en-us/community/posts/10436049566861-More-Year-Badges and https://support.khanacademy.org/hc/en-us/community/posts/10578518896141-New-Sun-Badges.

Also, I believe a KA Shop is needed, I mean a virtual shop where we can spend our energy points or maybe some other currencies. I have ideas here: https://support.khanacademy.org/hc/en-us/community/posts/10435923106445-KA-Shop.

It would also be cool to have some badges regarding the new streak system! They would be similar to the old clockwork badges.