What I would hate:
Ethereals being the only HQ. Price of Failure is expanded to affect more units, and with a debuff to boot.
Crisis Suits only have access to one short-ranged weapon, much like Stealth Suits now, but are still only 1-3.
Stealth Suits will have their SFG changed to just Stealth.
Vehicle prices don't change, but the wargear goes up in price.
Kroot lose Fieldcraft, and the +1 Attack on their guns.
Vespid get more expensive, but have their I reduced and/or their gun nerfed.
Carbines are reduced to 12" range and lose Pinning, but stay 2-handed and one shot. Pulse Rifles reduced to Bolters, Kroot Rifles reduced to lasguns.
Railguns get turned into Lascannons. Ion Cannons become Autocannon.
Fire Warriors get their Carapace Armor reduced to Flak Armor.
Of course, that's just being paranoid...