Making t2 pd cheaper buffs impulse defense which is already too strong in FAF and buffing t2 ACU does 0 to address the reality that Aeon ACU uniquely hard counters any land unit that does not have a sniper tag.
Cybran is the ACU that least benefits from having larger range as it has no real late t2 upgrade that buffs them nor any way to supplement the fact they are currently the weakest t2 stage. Arguing UEF should have a range upgrade is about as incoherent and cancerous as explaining why Aeon needs it. These are the best 2 t2 stages of the game, neither faction needs something that makes a strong segment of their game into an oppressive one.
All the faction lore logic is BS anyway. Cybran hoplite has more range and alpha than mongoose. They're the sneaky raid faction so their ACU would get the ability to do sneaky-free damage yet also be easy to catch out of position due to having no shields at all to act as an hp dump.