Working on putting together a treasure hunt, could use feedback on some ideas

I've been working on a plan for a local treasure hunt, but I could use some feedback. It'll be hosted through my youtube channel, and will most likely consist of a variety of hikes (some short, some longer, but nothing too crazy), some basic crypto, some cheesy poetry, and some treasure that I've made/will make as the prize.

So that's the nutshell explanation. I'm having trouble making decisions about some of the details. But first, let me go over some of the specifics I have worked out. My plan as of right now consists of the following:

• 5 hunts total, 4 that are similarly structured with 1 final hunt
• The first 4 hunts consist of 3 locations where clues are hidden, and one final location where the treasure is hidden
• The clue locations are revealed equally to everyone participating
• The clues are non-removable, difficult to destroy, so more than one can find them
• The clues are required to determine the final location of the treasure for that hunt
• The final hunt's locations can be determined by supplemental clues hidden in the first 4 hunts

I'm thinking of doing an episode per location, per week. Each episode will consist of searchable features like road signs and trailheads, followed by clips showing highlights of the path to the clue. If the clue is hidden to the general public, I'll show more or less where people can expect it. The clue itself will be a semi-permanent installation. That is, it'll be a physical form that's locked up somewhere for the duration of the hunt. After the hunt is over, I plan on going out and removing them. This is mostly because I don't want rogue hunters to destroy the clues so that no one else can find them. I plan on making a rule that if someone goes out and the clue isn't where it's supposed to be, I'll publicly post it. I doubt anyone would, but I still think it's a good idea to have a deterrent.

I wanted to get some outside perspective on how you think this would play out, and what sort of issues I'm missing as far as game mechanics.

• Would this be the kind of thing people would enjoy bringing friends along for, even though there's only one treasure per hunt? Is there some way I could make it more worthwhile to people playing in groups, without diminishing the value of effort for a single hunter?
• Would it be better to cluster the 3 locations for each hunt together? I feel like it might be more fun as an activity, but there's a much greater danger of making it too easy and having the first person out discover it. I like the idea of spreading the clues out time-wise and space-wise so that more people have an opportunity to take part.
• I have no idea how many people will participate. I have very few followers and almost all of them are friends. I'd like to try and promote it, but I also know that I'm pretty horrible at that sort of thing. Still, I'd like to come up with a design that would work well regardless if it's 5 people or 500 people playing. What sort of issues might happen as the player base scales up?
• I'm kinda going from scratch on these ideas. I've hosted basic treasure hunts before but nothing this complex. Mostly just "crack this cryptogram, figure out what the poem means, find the spot". This is basically the same thing, just with multiple locations required to find the spot. Are there other formats I should consider?
• Should the treasure be hidden? Or would it be better to send it to a winner? If it's hidden, it's probably way more satisfying for the person who finds it. But there's also a risk of someone random finding it. The hiding spots will have to be really good, but there's also a lot of people in this city who get out and about. Having a final problem to solve could be fun if it's done right, or it could be really annoying. I also don't really want to have to ship the pieces. And I think it adds in a dubious factor where people might be more inclined to question the legitimacy of the winner (which happens occasionally with online giveaway contest sort of things). I'm leaning toward just hiding the treasure, but I'm also open to ideas.

For context, not for self-promotion: I'm not really trying to plug my channel or anything like that, I genuinely could use feedback on this and I've really been digging the threads on here. If you feel like you want some context though, I'll put some links. I don't think they're necessary because I hope I explained it well enough and the videos don't really add anything, mostly because I made them before I started planning this. They're more like a weird, long intro.

It started because I was annoyed with my neighbor who kept asking for a favor, and to get sweet, petty revenge, I sent him on a treasure hunt. I liked the idea and wanted to make something similar for everyone else. It tied into a project theme I've been working on lately, so I started making a series of glass sculpture elementals, and introduced the artifact hunt with the first making-of video.

Planning on doing a video for the making of each piece, plus the videos for the hunts. It's gonna be a lot of work so I'm trying to get as much sorted out beforehand as I can. I've been really scratching my head over this for the past few weeks, so thanks in advance for any thoughts!