Something that I had always wanted to see was open world monsters that were more personable (I had fond memories of hunting down elites by myself in WoW vanilla, with my pet ofc, or doing NMs in FFXIV 1.0 when it was basically only you and one other person in the zone lol- something I can't quite "feel" in FFXIV since frankly it's too popular lol). As the game got more popular and the rewards for hunts continued to be worth while and easy to communicate around the train got bigger and bigger and the fights, imo, became a lot more attrition based and less interesting. I feel SE has tried hard to make them interesting still, but you've only so much balance you can muster in these situations so it's mostly a lot of "do the mechanics or die, and if too many don't die it either fail or take a really really long time" lol.
Similar reasons why I tend to think FATEs are just okay (though I felt a lot more rewarded and far less apathetic once SE added the Shared FATE idea in ShB), since this open group content usually has to face severe swings and balancing challenges to many or a few of god knows what roles, while on top of that the mechanics of the more rewarding ones tend to greatly frown on small to solo groups, which I find a little annoying. I love the open world, but I love to do it in small to solo size lol- FATEs and Hunts tend to be like "throw all the servers bodies at it" which tends to, imo, make less interesting mechanics and experience (I do hunts occasionally but strictly for the reward not for the gameplay experience, which is a major part of this pyre kindling idea to return some of that feeling).
So the short on the idea here was while the hunts will still scale a little bit they'll scale less than they do now (meaning smaller groups kill them faster). Spawning the monster and or killing the monster while 'alive' will grant you the chance at a lesser extra roll (so you'd get your standard rewards plus a reward into a different treasure pool as a bonus, balanced around that concept that it's 'a lil somthin extra'). Once the monster is dead their corpse will remain on the battlefield, slowly deteriorating (perhaps via pyre flies from FFX- that spirit trailing effect). You can check the corpse to see roughly how long it's been dead which can be used to roughly guess when it'll be back (monster will have three stages of decay, and a fourth state of limbo). Each stage will be about equally separated in time frame, with a final (fourth) stage that's just gone. Amount of time gone depending on type of monster and a slightly random small varying element (so if a monster had a 24 hour respawn, you might see 3 stages of 6 hours and then a final stage of 6 hours no corpse till respawn).
When you approach a monster that's fresh you'll be able to kindle the spirit at near-full power or lesser at your choice (Dark Souls bonefire imagery here lol), allowing you to fight them in a sort of instance of the area (fades/shatters out other monsters and non-party member players like a classic sRPG FF battle start, allowing you a fight on the open world but without all the noise of other players also fighting the same corpse

). Each stage represents a loss at a reward roll and a reduction in monster strength (able to choose weaker options but can't go greater than it's current state), such that a mostly decayed S rank monster could feasibly be solo'd (but you'd only get one roll to the rewards instead of all three, getting one of the possible rewards instead of all of them). A fresh S corpse would be 4 really good players or 8 okay players, of course you'd not get that extra roll but it's not a crazy huge loss either (those that find them alive/spawn get a little bonus, perhaps also make sure the spawners even if they don't make it in time for alive still get the "full reward" given they interact with the corpse soon enough).
I think in this it would be fun moment to add some more monster hunt concepts (more dodge-able attacks, but depending on freshness also more aggressive), monster parts (being able to craft housing and equipment, like DoL being able to harvest from certain corpses), as well as perhaps some other combat or relic content asking for the essence of certain monsters (keeping in mind it's now not that much of a pain to go find an S rank, if you tried). I mean to write more on it but I guess the general idea is to reduce the train strength while still rewarding those who go out and find monsters (may also encourage players to rush/compete against each other, capturing a little bit of that old hunting spirit), but here you could also now show up late (or have a slow console/computer) and still take part especially as the game gets more popular and the server walls weaken (I know some servers complain when the mega servers come in and kill all their hunts), or even be able to stumble upon something that causes players to go "woah...." and timidly interact with it.. which I think doesn't happen as often since players are tracking them and killing them. As the monsters don't need to be as strong now since they're not meant to be fought by 200 players and more players at different time schedules can take part- I think they can also add some experience rewards, a level 49 might be able to kill a level 50 A rank that's mostly decayed and get like 5% experience as a reward.
The super massive FATEs like Ixon can stay the way it is, though I think leaving some strange mark on the ground players could check for rough estimates on time of death would be nice (so like Ixon leaves a part of it's horn, or Odin it's sword- checking that would tell you roughly it's time to recharge/age of death). From the purpose of that hunt achievement I think only alive and fresh should count (making it slightly easier as if you missed the 'alive' hunt you're not really punished too much but not as easy as killing a fully decayed hunt). Semi-related but a more accessible hunting content I think would benefit a lot from having a refresh of our hunting log UI (
here), that it includes our daily, weekly hunt marks but also a baby bestiary of all the major B, A, S ranks of the areas (which could come with it's own rewards for filling
out, tracking which you've killed and such).
Technically doesn't need to be weekly but the purpose of a limit is to ensure their value (no limit means potential spam issues and potentially lesser value reward).