The field note drop rates and available windows for them to drop are pretty miserable. Waiting around for an hour killing rearguards trying to make sure the hypertuned havoc chain can spawn as soon as possible is not particularly fun or rewarding when rise of the supersoldiers yet again doesn't drop the note - or waiting around lunya's stand for help wanted and of fire and steel. Nor is entering the instances with the sole intention of running Castrum Lacus Litore or the Dalriada only to see it already underway. Bad RNG is not new to me - I have the big fish title - however with fishing there's few fish where you have to put in so much time babysitting the game.
There are several ways this could be addressed:
1. Severe reduction and/or removal of cooldowns and mob requirements on rare fate spawns. This would have a knock-on effect of making the duels come up more regularly, but as to whether or not that is a bad thing is another matter.
2. Increasing the minimum drop rate of notes to 20%. I don't know what it currently is, but it certainly feels less than that. Since the instances are also used for leveling, I don't think it would completely kill the zones, but I don't have data for that.
3. Implementing an RNG protection scheme similar to the weapon/mount totems from extreme trials. If all notes could be purchased from the historian after completion of the relevant skirmish for an arbitrary amount of coins (200 bozjan coins/rarity tier for example) then it would be an alternative for the 50 for absent friends with no note drop issue. Having them purchasable without doing the relevant fight doesn't sound correct so there might need to be some limit similar to the arr minion vendors that only show up after beating the fate chains (attack on highbridge etc)
d. Making CLL and Dal separately queueable. and maybe giving the tunnel borer echo so it's in with half a chance on extremely small party runs. This would probably require the most dev attention to implement and might be futile.