Here is my suggestion on how zombie players can be improved a little bit.

`

Undead - Your good ol' standard-issue zombified player, with their classic green color, and a few bruises. Nothing special, just idiot zombie players. You can summon this by dying normally.

Sunken - They seem to have learnt exactly how to use a trident, they will back away from any combatants that get too close whilst impaling them with tridents. Also has the classic aqua a normal drowned has, with decayed lungs. You can summon this by drowning.

Charred - Mastering the art of using fire, they will use any flint and steel they have to burn players, running away afterwards for a few seconds. They have a deep red color with burn marks in black. You can summon this by burning.

Retched - Stuck underground for so long, they have adapted to the art of using pickaxes to get to their target, by mining blocks in the way.
They have a monochrome dark grey color with an even darker shade of soot covering parts of their bodies. You can summon this by dying underground.

Wounded - They somehow have knowledge of how to use a shield, and will use any shields in the off-hand to block all attacks. They have a subtle orange coloring with wound marks scattered throughout. You can summon this only by dying whilst having a shield in the off-hand.

Shelled - They gained knowledge of the bow and crossbow from their cousins, the Skeletons, and so they will run away if the player gets too close, but somehow their arrows can grant the Infected effect. They have a darker aqua than that of Sunken, with an arrow wound in the chest. You can summon this by either dying to a skeleton or by having a bow in your main-hand when dying.

Starved - Their hunger for food means they will eat all food in their off-hand when on low health, because they have a never-ending hunger they will also move faster at the cost of less damage. They have a brownish tint with a decayed stomach. You can summon this by starving, which is one of the rarest ways to die in Minecraft.

Broken - They have a knowledge of ender pearls, using it when they are too far from their susceptible target. They have a light-purple coloring, with white scrapes across the legs. You can either summon this by dying to any End-related mob with an exception being the ender dragon (which will summon an Abandoned instead), dying when using an Ender Pearl, or dying to the void.

BOSS:

Abandoned - This boss zombie is spawned when you die in the End. After 5 minutes of respawning, they will spawn in the world with a very dark grey coloring with white emissive eyes. The Abandoned can use every zombie player variant's ability and AI, and will switch modes randomly. At low health, they will stop whatever they were currently doing, and roar, doing constant (but not overwhelming) knockback until defeated. Upon defeat, you can get any of the following:

Diamond Sword (Sharpness V, Knockback II)

Diamond Pickaxe (Efficiency V, Fortune III)

Diamond Axe (Efficiency V, Sharpness V)

Crossbow (Quick Charge III, Piercing V)

Enchanted Golden Apple (x10)

RECRUIT SYSTEM:

You can recruit a zombified player to your army by giving it 5 rotten flesh, it's simple as that.

The recuits have 4 different behaviours:

Neutral - Don't do anything.

Defensive - Attack only when you attack or are attacked.

Offensive - Attack no matter what.

Espionage - They will go up to the mobs, and then they will tell mobs something and make unrecruited zombified players and vanilla (and even untamed and or modded) mobs attack each other.
`

I would also like to ask if it is possible to give each variant custom animations?
(I also have a curseforge comment but that somehow got auto-flagged as spam)

It sounds like a cool idea for a mod, but I don't think I will be adding this to the mod, the only reason there are two variants is to keep parity with the vanilla game and zombie/drowned converting.

The most that may potentially be added is a husk player if I ever do something interesting with them, or potentially villager/horse drowneds at some point but I'm unsure if they will be.