Ice Lock needed more testing.
Ice Lock Conquest in my opinion adds nothing to the Conquest formula. Where it fundamentally goes wrong is that health regeneration is locked to standing 5 seconds near a flaming barrel. It completely destroys pacing and not in a good way. You're forced to give up your position constantly.
This is because every time you get into a firefight, if you take even the slightest amount of damage, you're forced to retreat to a barrel. Your medic buddy can't do anything about it, because health regeneration from crates/pouches is disabled. This is a problem because any frontline easily collapses and you're forcing people to group up in a small area with little cover where they can easily be shot. Yes, it promotes slower gameplay, but it simultaneously promotes gameplay that makes no tactical sense.
All the matches I've played so far are completely lopsided. Once a team is behind they can't seem to come back. This isn't weird, because the winning team can play defensively, while losing team constantly has to scramble for heat sources.
Warming up through sources other than barrels isn't a great success either. When a vehicle explodes and is on fire, it doesn't warm you up. Incendiary grenades have some limited success, but because you instantly get set on fire and you can't clearly determine when the fire will touch you, it has a significant chance of setting you on fire instead. Also, why are there challenges that force you to get into a freezing state? Isn't that the exact thing you want to avoid?
What could have been done about this? Perhaps they shouldn't have removed health regeneration from medic bags, even if you still have to get to a barrel to prevent the freezing effect from eventually damaging your health. Perhaps they could have given medics a "Flare" grenade, that allows players to throw down something that can warm you and your teammates up without hurting yourself.