I wanted to talk about one thought of mine that struck me today.
How about adding such an advancement (or group of such) which will work specifically past reaching your maximum idle time?
The idea is to provide a player with an option to continue getting some resources/armies/conquers/etc while you are gone for a long time and your idle time has being drained already and the game doesn't grind you anything while you are gone and don't come back and launch it once.
For example, my maximum idle time is 5 hours. (Due to some real life stuff, I began to go away for a lot and not coming back in 10-15 hours, thus my gamethrough is just stuck without any sign of progress, that's why I got such an idea, not really polished/thought out through or anything, just blank and stupid as I am :D)
So, when I go away for longer than 5 hours I stop getting ores, armies, producing alloys and items. The game just freezes for me until I come back. It'd be cool if there was such an advancement which will reward those players who are gone past their idle time limits with at least some % of their earnings (like, you get 5% of your mine/army camp/money income with 2.5% increasement per upgrade) or some flashy stuff like when you're past your idle time limit the game's speed is reduced by 95% (which you can upgrade till 50% for example), you still earn everything but at much slower pace!
Guys, what do you think about this? <3

Sounds cool, but would probably be a top-tier advancement.

When I first read your idea, I thought you meant to increase some timers but not all of them, like, after your 2 to x hours usual idle time ran out, you can still collect ores for some additional time OR craft for more time OR produce armies for a few minutes. So, in addition to the idle time advancement, a set of selected advancements only for armies ("Increased Idle Time for Armies"), ores ("Increased Idle Time for Ores"), smelter ("Increased Idle Time for Smelter") / crafter ("Increased Idle Time for Crafter"), money ("Increased Idle Time for Money") etc.

I like both ideas, yours and my misinterpretation.

^

+1