I'm Oninou on POE and the character's name is BarbERAn
Your Berserker has no Bleed removal on flasks and no curse removal flasks. No cast on damage taken set up either and 6K life but you are using Aspect of the Carnage which means you are closer to like 5K EHP. Also lacking in a defensive flask as well. In additional, you aren't running Flesh of Stone for additional mitigation/avoidance. No means of generating endurance charges here (can easily just attach Endurance Charge on Melee Stun on Leap Slam instead of Blood Magic which probably gets you killed with the Berserker degen as well).
Your Gladiator has no stun avoidance and below 6K HP. Also for some reason using a mana flask, no curse removal either on flask. No way to generate Endurance Charges on bosses which means a quarter of your ascendancies defense is rendered useless.
Can't seem to properly import the Deadeye character to PoB but you seem to have some weird, unnecessary nodes in them (two extra points in mana nodes that you don't need), 3 points in global accuracy as a Deadeye which you also don't need.
Main issue I am seeing across the characters is that only the bare minimum defenses are met and sometimes not even that much. Here are a few basic pointers:
*Always try to look for ways to generate Endurance Charges. Those 3 Endurance Charges help a lot. Any melee character can get easy access to Endurance Charges with Endurance Charge on Melee Stun on Leap Slam and/or Enduring Cry war cry.
*Always have ways to remove Bleeding, Freezing AND Curses. Curses are a big killer in maps especially Vulnerability, Elemental Weakness and Temportal Chains.
*Always have some way to avoid stuns as a melee character. Berserker has built in stun immunity but your Gladiator doesn't and that's like the #1 way to get killed in the game.
*You need defenses beyond just 6K life, flasks, fortify, leech and capped resistances. Flesh and Stone is big. Belt of the Deceiver is big because you take less crit damage (one of the most common ways to get killed). Defensive flasks, more ways of avoidance like block/dodge/evade or very high flat physical mitigation. If you have a character that can get high armour then invest in Molten Shell + Vaal Molten Shell. Artic Armour is a cheap aura to get for defense.
*You need ways to sustain back the HP lost. The new Doryani Vaal gem + Soul Tether is an easy way to raise your EHP AND have overleech sustain which is big. Life gain on hit on fast attacking skills and most Berserker builds can get you topped up real fast.
*Try to get a lot of dodge/evasion, a lot of block chance (one of the new jewels helps with this very easily) or get a ton of armour/physical mitigation and unwavering stance/iron reflexes. Secondary defenses are big. If you aren't using an unwavering stance then getting blind on your character (usually with Flesh and Stone) is big.
*You can have defensive curses as well attached to cast on damage taken. Enfeeble is the strongest one but Temporal Chains isn't bad either.
*Look for uniques that give powerful defense bonuses. Belt of the Deceiver is a cheap all around great belt for melee because it gives Intimidate on hit which is MORE damage and gives you less damage taken from crit, which is big defensively. Cold builds can take advantage of Pandemonius which reduces enemy action speed and blinds them. Phys taken as elemental damage is big defensively and can also roll on rare items as well. Some of the new timeless jewels provide a ton of strong defenses bonuses like Glancing Blows, Tempered by War, Divine Flesh etc. Loreweaves max resistances set to 78% is always powerful reliable. Hale Negator's ability to negate a % of your life based on abyss jewel is big.
My advice would be to play a defensive Trickster build to get a feel of stacked defenses. Go with Scourge Arrow CI Trickster using Hyri's Ire, many build guides on it. It has high Energy Shield (7-8K), Ghost Shrouds, huge evasion, dodge, leeching, recovery and other forms of avoidance not to mention it generally freezes anything it attacks for even better suvivabilty.