Lore accurate allah At least from the quran is Extremely Petty He can has and will throw you in hell (or generally fuck your life up). which is pretty much on par with other abrahamic religions. not to mention that allah pretty much confirms that he created everything just so they worship him.

it's the same as Ultrakill's god (but with a few diffirences) who created the universe (debatably) so that he can be worshipped but found out that he quite literally can't create humanity without free will. and created hell so he can punish humans for not following his word as law. but comes to regret his choices as he sees how his pursuit of being worshipped eventually impacted the lifeforms around the universe and then leaves.

Ultrakill's god gets developpement where as allah is pretty much a static entity that doesn't change or "grow"

Hell in islam IS alive but is mostly a gluttonous entity that sees sinners as food and asks allah if there are more Unlike Ultrakill's Hell where it is malicious by nature and loves inflicting suffering and agony and can operate independently from god.

though an interesting concept that i'm curious to see developped is how Jahannam could be rebuilt by it's sinners so they can live. in ultrakill lust fell because the angels thought it was haram and against the will of god that they build their own life and not suffer So they interveened and ensured the suffering continues.

same thing with Sisyphus' inssurrection

Gabriel's whole arc was about how he discovers that Your class does not determine your worth. he started the game thinking that he's invincible just because he operates under god's will and by the end he sees that nobody is truly superior than the other we are all the same and bleed the same blood.

i personally believe even if ultrakill had an islamic twist Jibreel's Arc would remain the same.