You just pointed out of everyone wants different things from the espionage. You will not reach a consensus, that's one, and two, forum dwellers are but a tiny fraction of Stellaris players. Even if you somehow managed to reach a consensus here, players from outside of the forum would not agree with this "consensus".
And you would be straight back to square one with people unhappy with the scope of the mechanics.
So your suggestion for the devs is "just do whatever, everyone will hate it anyway".
Not really constructive, i think.
As mentioned in some posts already, configurable espionage settings might be a good step. (Similarly to how Xeno-Compatibility can be turned on and off. Even though that had other reasons.)
So you can have the whole range of super disruptive assassinations and economy crippling sabotage to less disruptive means.
I mean, i can see why the devs wouldn't want that, since it would be essentially two different game modes that would have to be somewhat balanced seperately.
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