What About Individual Challenges?
I love group challenges as much as the next Communist where I can chill and have other trainers put in the work and reap the rewards for everyone. But what about Individual Challenges? Now hear me out this can be pretty cool. What if we had an individual challenge to catch 1000 Pokémon in 7 days and when you reached that Goal Lt. Surge appears! He makes some catchy quote like “Hey, kid! Who do you think you are traveling all over and catching them all? How about a Real Challenge!” He notices you are a Trainer worthy of his challenge and you go into a 1v1 fight with him. He makes a lineup of 6 Pokémon that you can’t see “for anyone who played the games would know it would mostly be electric” and you pick your heavy hitters and you go at it. If you win you are rewarded a Kangaskhan! And a medal that stated you defeated Lt Surge during the Travel Event.
But seriously Niantic can do so many things to make this game fun.

Answers
Individual Challenges or Daily Challenges have been suggested many times.
Kangaskhan as a reward sucks. He has already been a reward at many events everywhere (more than any other regional), and is about to be released again during another event. Perhaps something Australians might be interested in may be a better reward - as we have had zero events in the entire country for us to get other regionals, while our regional has been everywhere already.
SIDE NOTE There is a big difference between working together and Communism - team work and assisting a fellow human is not a political ideaology...but that confusion of definition explains a lot.