BUILDINGS ARE NEVER MADE ALONE... Are they??
(Read last line for the main idea if you don't have enough time)
I had this idea for long and I think it's might turn out to be the game changer for some players.
The buildings' upgrades take a lot of time after reaching a certain level. This makes the game boring (atleast I think so).
My idea came from the concept of team work. When builders work in a group as in reality, why not in the game. I think there should be an update allowing us to employ more than one builder at a time for one building upgrade or construction. This would not only make the game faster (as we'll have a lot to do and less to wait.. Lesser than before ) but also give more options on part of planning.
In a nutshell, it should be allowed to employ more than one builder for buildings' upgrades or construction.