I think that "Find Familiar" kicks this spell off. Why should it worth a 6 th. spellslot? Well... as Mithrandir wrote, Homonculus should have be more usefull. Like; it is able to talk, write, has the creator's perception, or even available to cast minor spells (on low spell level like cantrips or 1. level spells), change shape, share senses (like warlock's Find Familiar does), or even available to use greater invisibility on self ... in this state I think this spell is very underpowered.

Wouldn't it be usefull in a combat situation when the creator would die, but the Homonculus jumps in the front of the strike and protects its creator with the transfered health, use Help as action while invisible, or meets a party member and tells the creators words while he sees through its senses that the creator is trapped, or in danger? 

I also feel that the Homunculus should be a little more useful, but now that I look at it there are some important differences between this and a familiar. 

For one the Homunculus can attack (pitiful, but something the familiar cannot do).

Also the share senses is different from a familiar's.  In order to see through the familiar's senses, the spellcaster has to use an action.  This does not seem to be the case with a Homunuculus.   

Consider as well [Tooltip Not Found], for those who wish to make their homunculus more interesting.

A cleric of the Arcana domain can get the spell with their level 17 capstone ability.

Given that a wizard academy would have the ingredients and skill you need (including the dagger), I am sure that they would have a way to grant you one. (say magic jar the wizard into your body, then send you back.)

Does the poison/unconscious effect work on creatures immune to poison? Or is the damage type and status effect different?

Everyone I've ever met says this thing is pretty ugly and there could be literally any other companion that you could use. Personally, I think this is the cutest thing ever and no one can change my mind.

Most likely no one will see this, but if they do:
"Telepathic Bond. While the homunculus is on the same plane of existence as its master, it can magically convey what it senses to its master, and the two can communicate telepathically."
Does this mean that it can convey what it hears, sees, smells, tastes, etc to it's master? The word "senses" seems a bit vague to me.

I want one desperately, and I'm not willing to wait until my wizard is level 11 to get one. I will beg the DM to let me have it at the start of the game. It is the most adorable little derp on the face of the Earth and I love it to bits. I will name him Gibby.

I believe that your personal Gibby can share its senses with you. The reasoning is that telepathy surpasses any "lost in translation" or mandela effects in that the exact idea is communicated directly to another's mind. Instead of describing a smell, you can put the sensation (as you remember it) directly into the person you're communicating with. With this in mind, Gibbies can put their direct experiences into your mind.

why not just find familiar a quasit or something

Quote from TheChangelingRanger >>

How long qould a homonculous live?

 As long as its creator

Why does everyone say this is an underpowered ability? You only cast the spell once, then you have a permanent "better" familiar from a scouting, messaging, and possibly even max attuanable item perspective. Yes Find Familiar still has some strengths over this guy. But unlike the Familiar this is a complete additional set of eyes.

Are there other "better" 6th level spells, absolutely. But there are only a few spells in the entire game with permanent ongoing effects that do not require concentration.

While this is  better than the average familiar, remember warlocks pact of the chain, which you get at third level. I still like this, but pact of the chain is better in my opinion.

Yes, the arcana Cleric. However, that isn't until like tier 4 I think.

Quote from RegaLewis >>

Would a cleric be able to create a homunculus? 

 you could use the feat ritual caster and then take the spell to create the homunculus and cast it as a ritual instead of a normal spell

A cleric of the Arcana domain can pick this spell up. However, the feature required is only gained at 17th level, so I wouldn’t count on it.

A familiar, 1st level spell, can help you in combat, cast touch spells, and work as a scout so long as you use your action each turn to see its senses and it's within 100 feet. A homunculus, a 6th level spell, gives you an entire extra set of senses to use without limitation so long as your homunculus lives. You can scout ahead across an entire plane, spy on people, avoid blindness and deafness in combat, keep an extra eye out from above, cast spells that involve sight to where you homunculus can see rather than just where you can see, follow enemies to always know where they are without limitation, and just general practicality in combat. A familiar is so much more limited because its senses require an action to use and its bond only stretches 100 feet; this just costs 1 spell known and a single 6th level spell slot so long as your homunculus evades death. A familiar might still be good to have (you can have both!) for purposes of using spells with them, but otherwise homunculi are extremely powerful in many contexts. 

Definitely worth considering! For your character or any NPC you run as a DM.

Craziest little compagnions ngl. Even though most of them turn out to be kinda nuts in every single campaign i've been, they're so great.

Quote from TheChangelingRanger >>

How long qould a homonculous live?

 As long as it’s maker does. No limits beyond that