Looking for a good sci-fi book or LitRPG (id even take zombie apocalypse at this point)

I feel like i've read most of the good sci-fi out there! I love space opera/space marine stuff. We are Legion is one of my favorites, Undying Mercenaries, Expeditionary Force, Hell Divers, Peacemaker Wars, The Primal Hunter is my absolute favorite series, Dungeon Crawler Carl etc. I'm looking for a new series (ideally) but really any suggestions of good Space Marine/opera stuff, good LitRPG's, even post apocalyptic or zombie apocalypse. I have around 1000 books in my library and I feel like i'm coming up empty looking for something new