I think the game is under constant development.
I suggest a new building, calling “bank”.
The player could define to collect X% of his incomes (ham, iron, even heroes, troops, emblems, battle items, maybe others) automatically in the bank.
I mean, you could better collect resources for big upgrades or challenges with this function, while you could do the “daily” building/hero/troop/etc. upgrade undisturbed.
Even trainer heroes/troops/emblems/etc. could be collected for a planned greater upgrade.
Automatically would mean like “10% of…” or “every fifth dark”, etc.
Direct debits would be possible, too.
This new building (what about having this as a part of the “static” Stronghold castle???) would enable applying new tactics and strategies, while giving more fun for every player.