I post this on the event feedback regularly but I'm going to post it in an actual suggestion thread as well because it feels like that thread is just never read (that is a discussion for another time though).
If there is a leaderboard for an event, the base minimum we should be told is if there are prizes and where the tiers are for those prizes. Is it the same prize for all 50 or do I have to aim for top 25 to get everything? Tiers are important knowledge (they don't have to exist, I like it when they don't, I understand why they do sometimes, but we have to know if they do). I always assume there are, but sometimes I'm wrong and I shouldn't have to ask in the SB to be sure.
Additionally, and I can see the argument for both ways, we should know what those prizes are. I'm personally far more likely to try to get to a tier with a book or squishy or food. Other people are more likely for a nice little toy and many will fight tooth and nail for clothing. I think you actually get more overall engagement if you reveal the prizes right at the start because people will fight for what they want. Even if FOMO is what pushes us when we don't know, that's much more stressful and a far more negative feeling than "I want this item that I know I like" and more likely to end in disappointment when the top tier item is something we don't care about at all. That's just my take but either way, the next point is the important thing.
Some users know what these prizes are. Yes, those users are staff and I understand why they need to know, however, they can join the leaderboard the same way as everyone else. This means they have the inherent advantage of knowing whether they want to invest their time/energy/TU into this endeavor. Unless there is a very pressing reason why regular users can't know what the prizes are (brand new feature? I can't really think of any other solid reason) if someone that can participate in the same leaderboard is allowed to have more knowledge about that thing that the other people can't get through trial/error or finding it somewhere on the site it's inherently unfair. I am not advocating that staff not be allowed to play the event, not even close, I am just saying that regular users should at the very least be given the same playing field. I recognize that staff will inherently have some advantages over regular users just by virtue of knowing things like features that are coming up but this is a very easy and harmless playing field to level.
If the concern is that some people like not knowing (who am I to judge if that's what they want?) then it's still a simple fix. The prizes could be a separate page like they are for every permanent quest on Res or just a dropdown that opens like the color hatch chances in the hatchery.
This is kind of a tacked-on afterthought but this goes for games too. Things like Treasure Hunt. If you don't ask in the SB or find a user-made forum (which didn't exist until super recently, probably because someone was frustrated with not knowing) you don't even know that you can get "bonus" RC from stats or what those stats are or what the bonus limit is. It should be clearly stated somewhere within the game page "Your pet can find up to 5 bonus base RC, one extra RC for every 100 stats combined in agility/power." Worded better of course, I'm just throwing up whatever first comes into my head for this example.
Places the game transparency could be useful (this is not all-inclusive, just ideas):
Enchanted Springs tier rewards
Treasure Hunter stats/max bonus
Quests listing which shops they pull from somewhere obvious
Whether different tiers of the easter egg quest give different squishies (event-only game obviously)
Full list of all things we can find while on the egg hunt page for the event (also event-only)
Edit for clarity: I'm not suggesting telling people about events in advance, just what the prizes for the events are completely clear once it releases to the public and what position on the leaderboard you have to be to get there.
Edit 2: We now know the prizes for the event when this was written. I'm leaving the first part here because this should be standard 100% of the time so it's mostly there as a reminder. In fact, it'd be nice if it was somewhere front and center on the leaderboard page or somewhere easily accessed from it so we don't have to dig through updates, but the update is good as a bare minimum and enough to go on. This thread isn't "done" yet though because the second suggestion is not yet implemented.