Increase the spawning window time.
More allied seals, less allied seals, couldn't care less.
Increase the range at which monsters spawn, remove the grind from them and increase the hunting/searching/RNGingn aspect of hunts.
I say, from 2 to 6 hours after death, there's a random chance the A rank might spawn.
S Ranks are ok, I guess.
What will this do? Players won't spend 2 hours in a row killing all the open windows and then waiting 1 hour for them to spawn again, rinse repeat. Instead, players who search frequently/randomly will be rewarded (and leeches won't be so rewarded because they're not expecting hunts every minute of the day and get caught off surprise/stuck in a duty). Those who expect hunts to be a farm, will be left disappointed and curse RNGesus.