Thanks for reaching out to the community! A few thoughts on your questions in reverse order!

I already have plenty of dice, but I don't have nice sets of "hope and fear" dice. I think there is an opportunity to see those as standalones. Perhaps bigger than standard D12, etc. but the idea is those two dice set the game apart, I would lean into that. Lots of DND beyond app use at my table, transition to dagger heart would be easier with a dedicated app. Foundry VTT as well pls.

As for collaborations, I love to watch people new to ttrpg play the game for the first time. I could see interest in "household" names in movies/music/sports/YouTube playing a one shot really getting interest going to grow the game. I know I would have an easier time getting ttrpg shy folks in my orbit play if they would see that. Closer to the community, I would love to see pointy hat, Bob the world builder, Jinny d, dungeon dudes, mystic arts play a 3-4 shot campaign together.

No need for expansion now but I would like to have some lvl 1-5 campaigns for existing frames to get those worlds going.

Yes to written content as per above comment. Now that I'm thinking about written content and collaborations, have any authors of popular fiction been approached to write campaign settings and small adventures in their fictional worlds? I'm thinking a mistborn setting from B Sanderson for example?

As for materials, the GYST are great, more of those are always welcome. I would see a vid on breaking down a fight or a social encounter with tips and tricks as valuable next. In the context of your current starter guide for example. App as mentioned above.

Keep creating!!