As for the button to select units quickly:
almost all RTS videogames offer the ability to quickly select a group of units previously indicated and stored under a "keyboard code".
It's not a matter of having different buttons from the other players, but it's about selecting the units you want, with 1 click ... instead of losing 5 minutes to select each unit type you have in your bunker the exact amount you want.
Watch this video for more details:
https://www.youtube.com/watch?v=dBlNRfFkPdk
honestly I do not think it's a complicated thing to develop:
when I am on the unit selection table, I press "1" on the keyboard and automatically select 10 firedrake, 100 mauler and 100 sapper, rather than scrolling through the unit selection table and selecting them maually.
something like that...
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Regarding the possibility of reconning the incoming attack by the defensive player:
first of all, the spying would take place only 2 minutes before the attacker hits, so the defensive player would only benefit from the information if he is online at that precise moment and acts quickly.
second: if you think that the possibility for the defender to spy on the attacker's army is so ruinous for the game, why do you not consider the attacker's chance to spy the forces of the defender equally damaging to the game?
I do not understand why it is unacceptable that the defender knows in advance what he is going to face, while it is considered legitimate for the attacker to acquire this information before hitting an enemy base with his army (knowing in avance the defensive forces contained in it).
The interest to attack will not be killed at all: the players will continue to attack trying not to be reconned (as well as the defenders will defend the bases, trying not to be spied on).
Again, the strategy will not be dead at all, but rather it would become more elaborate, allowing players to develop new game tactics and pay more attention to developing attack strategies.
your usual conclusion of an impoverishment of the strategy makes no sense.
if the chances of action increase, the strategy also increases.
rather it is currently that there is no possibility of implementing strategies.
the only possible strategy currently applicable is to deploy as many defensive forces as you can, hoping to be stronger than your attacker (that's all.... which, honestly, is not a real strategy).
By introducing this change, then yes, you can start talking about "strategies".
So it's exactly the opposite of your conclusions.