An article for the beginning only, but I think you will find it most useful.
The buildings as above – C, L, N, U, K, S, O, D, I, X
or
With all these latter you cannot find the buildings on the map, but only give the order to build them. So you have to "find a citizen" - ". (dot)"- to give him the order to build "B" (BB for military or BBB for wonders, or W for wonders and Z for military) and then to press the key for the building e.g. "E" for to build temple.
The most useful combinations as for me are C-V-Q at the beginning of the game. You give the order in your city "C" to train citizens "V" as long as you have food "Q" (for infinite queue). This infinite queue is very useful but can be dangerous too. In the time your unit is being trained you accumulate resources for the next one or just use them elsewhere. But don't forget to switch it off This happens automatically when you are short on resources for this unit.
The next useful thing L-T for find library "L" and research science "T" (or "R"-commerce, "E"- civic, "W" - military, "Q" -age up).
So the beginning of the game looks like this usually: "C-V-Q-A-L-T-' " which means:
In the city C train citizens infinite V-Q and send them to all economy objects A, then in the library L research science T, then find scout "' " and now you are ready to give the move orders for your scout.
To press all the keys, you only need 2-3 seconds. In the rest of the game I always combine the keys and the mouse. It seems to be faster for me. Like L for library but then mouse click on the research in it.
The next useful things for the beginning are: "shift+," - all military; "shift + ." all idle citizens.
That shift key means "all of the kind" like "shift – U" all universities. Then "V" to train a scholar there and then "Q" to infinite queu them. Or "shift+K" all barracks- mouse click on the unit kind to train and "Q" to infinite queue them if needed. They stop building when you are short on resources for them, or when you are at population limit, or if you press "Q" again to terminate the infinite queue.
Use the "tab-key" for to find available upgrades and to circle through them.
Pick a unit and press "home" (Pos1) key to select all the units of this kind you have.
"ctrl+home" - select injured units and i.e. send them to heal in a castle.
To order the selected units to attack citizens as priority use the raid stance "shift+R" or to switch to aggressive "shift+A" or to hold fire "shift+H" (very useful for an ambush).
No delay for citizens and build or gather order at once.
Aggressive stance for the military units training buildings.
Assign "P" not for pause but for forts, to train spies is easier and also prevents accidental pauses.
Even if you only use the initial sequence of "C-V-Q-A-L-T-' " this speeds up the game immense. Try it yourself.
Since I am still learning the keys I will continue this file
I_.Lion