I do like the idea of increasing the number of mythics available per week (5 is very reasonable)
For fun, ran the numbers. This is meant to be an objective observation, so any conclusions are your own:
There are currently 64 mythics in the game. 3 of which are permanent (EK, Zuul and Xathenos), and 1 which is Sacred Treasure. That leaves 60 actual mythics.
At a cycle of 4 every week, that takes 15 weeks to complete, just a little over 3 months.
We’re about to start another cycle in next week, meaning that these next 15 weeks will cover 4 new mythic releases (February, March, April and May). We’ll also finish the current campaign. Since the new May mythic is released at the end, we won’t see it in the current cycle, but we should be seeing Quetzalma, since it will have been released more than 4 weeks before the end of the mythic cycle (a theory that would be confirmed if we seen Queen Nefertani shows up next week to finish the current cycle).
All that to say that instead of a 15 week cycle, we’ll have a 16 week cycle (due to 4 new mythics), ending on the week of May 17th.
The following 16-week cycle would end on Sept 6th, spanning (June, July, August, September) and 2 campaign mythics. While we can exclude September and the 2nd campaign mythic, the May mythic and Quetzalma will be added to the mix, leading to 6 new mythics in the cycle, pushing it to 17.5 weeks, ending instead on the week of Sept 20th (although this week will have started a new cycle).
At 4 mythics per week, Jan 2022 will be a 20-week cycle, or 2 cycles per year. A possible comparison would be the kingdom cycle, which is 34-weeks long, or 1.5 cycles per year.
At 5 mythics per week, currently we’d have a 12-week cycle, during which we’d add 3-4 mythics, increasing it to 13-week. This would further increase to 15 weeks and start 2022 as a 17-week cycle. Yet, since the nature of the game is to keep adding more mythics, the number would have to be continuously adjusted to keep the cycle constant.
TLDR: At current rate of 4 mythics per week, by Jan 2022, you’d have to wait 20 weeks for a specific mythic to return. At 5 mythics per week, you’d have to wait 17.