The wanderer's companion support add-on?

I remember before the season, a friend had me on pet sitting, and watching the house while they were away. This friend also handed over the sacred code to access his windows, in a subtle hint to get lillith statues before season begins.
Not only netflix would not give me mel brooks, they made robocop non-existent, and only had one terminator in their stream search. Needlessly to say I was bored and heard the horns of Diablo like it were drums of Jumanji.
Not only I did get the statues, I turned their character into a T3 Helltide surfer by the time they got back.

So it brings me to the idea of something that isn’t often seen in games, battle buddy idle system. Dragon’s Dogma is a great example of what I’m leaning to, except instead of a familiar you create and share, it’s a listed friends Diablo character.

Rules to the Wanderer’s companion?

Your wanderer can have only one of these companions at any time.
Companion can only farm 1\4 your session of xp (Lvling or season points).
Companion must dissapate/explode/die if friend is logging into game.
Companion is a one way mule pack, YOU CANNOT unpack gear you dumped into the companions inventory. Also you cannot dump consummables or quest items, etc.
Companion equipment remains unchanged, there will be no auto equip function.
Companion is updated once daily by friend using the character. (Ex friend logs in frequently, but his character will not be updated until the 0 hundred hour mark).
Companion can only use the skillset that is configured on updated. (Since there are npcs fighting in open world, I believe this is possible.)
Your companion has to complete the capstone dungeons to go further into the WT with you.

This should help in preventing any extreme exploits.

So after reading that. You ask “Why would I bother? What boon is there for me if I carry my companion around?”

Companion can be an added number to party without ramping up monster difficulty. XP gain factor and buffer/tank/cc if skillset configured.
Your friends may take your character as companion. Gold, XP, dumped gear collected while offline. Also if legendaries dropped, it will be added to your stash as missed items like it currently does.
When your companion dies, it doesn’t effect durability. Ex your companion was murdered by a falling ball of magma in helltide. You can text friend how weak they are without them wigging out on gear wear. Vice versa if your char are the weakest link.
Your companion can also share other assortments of buffs on shrine activation. if you have conduit, your companion can have protection, greed, blast wave shared with you.
Your companion may look silly with random npc chatter. (honestly an idea, but be funny if characters were more like our sidekicks in D3)

It’s an idea stuck in the brainpan since, I figure it was time to share this content idea to the community to see what you all think on the matter. Would it be desired as a Add on feature? If yes, any idea on improvements or possible exploits can be argued as terrible?