These ailments seem to be the same old stuff we see in every ARPG. Chill is to slow and basically build up to Freeze, Shock increases damage in some way. Even Ignite and Bleed are basically the same just with different damage type. I think Last Epoch can do better than this.
Shock
Shock could be something that does lightning damage, but also strikes nearby enemies that also have shock. The stacks of Shock can increase frequency of the strike between enemies and also increase the damage done by Shock. If Shock gets to x stacks (say 15), then the enemy gets Electrified. Electrified enemies will shock strike nearby enemies dealing damage equal to the stacks of Shock on the Electrified enemy.
This would make Shock better for AOE skills and still be useful for bosses.
Chill
We don’t need speed reductions on Chill, that can be done on Slow. Chill could do a cold dot that is skewed. Say Chill lasts for 4 seconds, the first second could be 5% of the overall chill damage, 2nd: 15%, 3rd: 30% and the last tick could do the rest of the overall damage. But we can go further, make the last tick be amplified by the amount of stacks of Chill on the enemy, and remove all the stacks.
This would make Chill better for faster attacks to apply more stacks before the last tick.
Ignite
Ignite is pretty straight forward. Maybe reduce the damage a bit but allow it to do fire damage to nearby enemies. It would still be a consistent DoT but will be useful for both single target and AOE skills.
Bleed
Bleed can have something extra too. Every 10 stacks could add a stack of Haemorrhage that speeds up the Bleed damage while making them expire faster. The more stacks of Haemorrhage on the enemy, the harder it will be for the player to maintain bleeds on them.
This gives players a crazy Attacks per Second target to do massive damage and maintain the Haemorrhage stacks.