Basically, what all you need to put:
What's the name of the transformation that your user calls the alien,
Any defining/different features or uniform your alien wears
Omnitrix placement
(Yes despite my dislike of OP stuff Alien X is still in my Omnitrix)
For me
-Name: Cosmos
-Features: Build similar to OV's design (including chin), a beard similar to that of Starbeard, Clothing seems to be a mix of Starbeard's and a greek philosopher, aside from his clothes and keys his entire body has the Chowder effect with space (character moves over pattern instead of pattern moving with them), still has the two personalities named Calvinus (Purple masculine face with an aggressive-looking beard) and Amora (Purple softer face with a soft-looking beard), his personalities are just physical representation of his mind and are more like the angel and demon on ones shoulder (sorta like the canon), when speaking all three voices speak at once but one voice can speak at a time when that personality is taking control which also effects appearnce
-Calcinus speaking: more masculine and muscular with the uniform representing armor
-Amora speaking: body more slender with the uniform representing cloth
-Hunter (aka user/third voice): resembles my own appearance with the uniform looking like normal Cosmos's
Cosmos has all the weaknesses DJW has said regardless if a joke or serious and the reason is because Celestialsapiens aren't naturally immune to everything but could become immune by choice/agreement, Cosmos is also weak to the Annihilarrgh due to him technically being born within a Universe rather than in the forge
-Omnitrix Placement: Chest not on clothing/uniform
Fun fact: A deal was already struck to allow freedom of movement and speech, meaning they are more likely to agree to basic things, but when doing son that is huge (example like reversing a destroyed damn) Cosmos will be motionless for a while or more to reach agreement (the more serious the longer the debate)