So I know simplified overhaul is an oxymoron but I mean simple by not changing his abilities, but adding to them to change his place in the game.
So the concept is based on Inaros being a Pharoah/Anubis like figure and Egyptian mythos and death practices where the importance of being buried with wealth grants you a better afterlife.
Passive:
So the passive of him dying and being able to revive himself would remain the same, but have the damage based on how many credits Inaros has picked up since he lasted went down on top of it being maybe more percent based so he can revive even in steel path. This gives it better scaling for mid to endgame and works in tandem with other changes to his kit
Desiccation: the buff to his first is that enemies killed with this buff active gives increased credit drops, allowing him to build up his coffers before goes down.
Devour:
the buff to this one is while he devours, he also begins looting them and stripping them of their wealth to deny them a good afterlife. The idea is it would work similar to how ivaras stealth works where as you devour them they are dropping loot, and allowing him to find a place in the looting meta but more focused then hydroid or nekros, better for farming mod drops and specific individual drops.
Sandstorm:
Not as much to change though maybe consider having the augment be base ability
Scarab armor:
Main buff to the ability is that similar to the augment where it is consumed on status prevention, have the ability be consumed to buff his other abilities, increasing the range and duration of his desiccation, spending up the time his devour takes, and sandstorm applying the desiccation effect to those in range.
The main take on this one was to avoid changing him too much where he feels like a new warframe, while still allowing him to find his place in the game that makes him viable and useful to a team, and making him more of a loot focused frame is something everyone can benefit from while still fitting with the Egyptian undying Pharoah them.
If you have suggestions as to how to balance or improve my ideas let me know.