Cyclone berserker in 2.6 is somewhere around 6-6.5 K hp with VP and is basically immortal. With 3.0, you should be able to get at least another 1-1.5 K hp. Additionally, Berserker can also use CWDT-spells with Cloaked in savagery so that the only thing that can kill you are 1-shots and degens. For HC, Berserker is definitely the safest version.

Slayer should have more aoe and will therefor be a bit less clunky. It's leech not stopping at full life can give pseudo-vaal pact like effect.

Juggernaut kind of sucks for cyclone. Specifically, it doesn't have bonus AoE like slayer has. It doesn't have leech that slayer or berserker have. It's tankiness comes from regen, which means that if you are about to die, you have to run away, which means you aren't doing damage. In effect, regen caps how many enemies you can fight at once, whereas leech scales with how many enemies you are fighting since more enemies = more damage done = more leeching.

Raider is the other option to consider. It will have by far the most movement speed, and for some that will be enough to overcome the fact that it is much less tanky than the other options.