What about build queue saving?
Pressing Ctrl + [Number] in city screen to save
Then pressing [Number] again to load
And the nicest thing is that this is persistent from game to game as well
For example, I save my queue like this:
[1] - 4 x main city attacker
[2] - 4 x siege
[3] - various stack defenders (e.g. 1 x pike, 1 x mace, 1 x longbow, 1 x crossbow)
[4] - 2 x main city defender
[0] - basic infra (things that you usually want in every city anyway - e.g. monument, granary, forge, lighthouse, factory, library, market, barrack)
Tips on creating the building queue is to start a game, go into world builder to enable all tech. Then create a coastal city to generate that building queue.
Now when i start new city in game, I just hit [0]. Then maybe spend a bit of time to remove things that I may not want.
When going for war, I just put 2 cities on [1], 2 more on [2], 1 on [3], and the rest (usually cities with lower production capabilities) on [4]
Then you only have to update the key [1] - [4] when you get new major military tech.
As for the basic infra, usually you don't have to update that at all.