WN translation just completed at the end of chapter 22 TODAY as well (coincident ???), havent read pass chapter 15 so no ideal how its going at the end, but reading WN make me understand story line better than manga, that for sure. Characters feel more dept . It feel like real OP returnee-isekai than pseudo-shounen like manga (MC turn super saiyan to fight like wtf ?).
There is much more variety of characters , like the voice actress arc (more like whole chapter), exchange school program with Red boi and Blue girl arc, childhood friend ojou-sama arc, Nord's soldier island training arc, or MC bull-dozing entire JPese's anti-variants organization HQ just bcs the elder dont let Futaba go after tricked her join it (yes, he seriously DRILL through floors to get to the elder at lowest level and very ANGRY. Lets say it close to how Saitama attack Boros's ship in OPM. )
And Susanoo's sacrifice feel much more logical in WN. He get decap in previous battle against the traitor god, but somehow JP Organization bring his head to its HQ, and in final fight between MC and elder, he use his last amount of mana to bring out Kusanagi , stab the elder while getting assimilated in elder's body, saving his bio daughter Futaba-hime and MC. Not randomly appear as a ghost like in manga.
Here is WN translation, the translator is well know for his work for translating Farming in Another world (Isekai Nonbiri Nouka)
https://www.shmtranslations.com/completed/transmigrated-salary-man-in-his-40s-returns/