In Hot topics Q&A (July 2017) this is the answer from SP I think on our questions on what happened in 72hour challenge and what is happening in the maze.
Although I think change can be good and for many of us it became a routine to do some stuff the same way like saving gold/growing food for 72 hour challenge and breeding thunder eagles for maze (we are creatures of habit after all).
A little warning before a challenge starts would be nice.
Also a 72hour challenge is a little short to figure out what does work especially for the the higher levels that have a more difficult time to gather coins and although I dont expect to get all monsters it would be nice to get at least one and not having to spent 24/3 at the game (some of us do have other things to do).
Changes in breeding and hatching in the maze I dont have a problem with that although again a warning/hint would be nice some beginners ask advise here, fb reddit etc and there whole groups who are misinformed now and we (I) don't give hacks or shortcuts but advise how to approach an event.
I know SP is working on many things but it would also be nice to inform us before an event starts specially with a short timed event and maybe a little hint on where we should concentrate on ;)