The perks overlapping is entirely intentional. One of them requires an ascension path, one of them requires an ascension path, and the last is locked behind two rare technologies (the first of which being Chemical Bliss, which is often skipped, and the second being tier 4 with weight 20). In the early/early mid game, I'd go as far to say that it's more common for an empire to have unlocked none of these than it is for them to have unlocked one or more.One potential issue is that +4 Encryption would make the overlap between the population control edicts more problematic. Since the effects from relative encryption cap at +4, getting multiple +4 bonuses would be pointless. Empires would then be encouraged to pick no more than one of these edicts. At least if Encryption remains the main bonus.
It now also just occurred to me that it would be conceptually reasonable for Information Quarantine to also offer an Encryption bonus. If that edict is changed to also include an Encryption bonus, the overlap issue could become even bigger.
But it is also pretty easy for an empire to stack Codebreaking. Bureau of Espionage (+2), Going Psionic (+2), Subterfuge tree (+2), civic combos (+2 for normal or megacorp), whisperers in the void shroud pact (+2). A psionic empire focused on espionage can get +10 codebreaking. Even using all three edicts in that situation wouldn't be enough to max out relative encryption (although with the +2 encryption from going psionic yourself, it would).
Going full espionage is a bit of a meme (and likely still will be even after it's buffed), and that level of encryption would be gross overkill for any other empire fool enough to attempt infiltration on you. But if a player wants to say "You shall not spy on me", I think they should be able to have that option. More realistically, you would just use one of them to significantly hamper espionage efforts.
Information Quarantine is about inward protection of information, keeping your populace from learning about wrong ways to live their life, not about preventing information from getting out to other empires. While I could see a point of encryption being tacked on, it shouldn't be more than that, and the edict is already very strong so the cost might need to be raised if that was done.
Remember that all three of the -happiness edicts were originally added in the espionage update. Making them not about espionage just feels weird and wrong.
- 1