When writing out the Monthly Quest this time (awesome idea, by the way, about the Christmas colors), I realized that what we're doing is pretty revaluing shinies to certain weighted values; ie., red and green shinies count as 1 but all other shinies count as 0 for this month. I think we can do a lot with that, playing with the values to add more stuff to the Quests. Like, we could try randomly assigning different values to different groups and letting people hunt normally, seeing what shinies they get and then valuing them accordingly. This would let people hunt whoever they want and would reward people for getting more shinies. For example, if someone is looking for a particular shiny to complete a Quest but accidentally runs into a different one, that has no value under the current arrangement. But if we assigned a random number from 1-17 to each type, we could have people go about hunting in a way that encourages people to search for the type that's valued at 17, but it would still reward someone who has 2 9-value shinies over someone who only caught one 17.
Just a crazy idea to throw out there, figured I'd see what you thought. Then again, it's 4:13 AM and I'm probably just rambling, "lol."