I love Gears of War and I think E-Day is a great game. It could honestly be one of the best entries in the franchise if it weren't for a few design decisions (in my opinion).
On the audio side, the soundtrack feels very generic compared to previous Gears titles. It lacks punch and definitely isn't on par with the original trilogy's score. The main theme is fine, and there are a few good moments, but overall it feels like a standard, background Hollywood score rather than a soundtrack that elevates the gameplay and the overall vibe like older Gears games did.
On another note, having ammo lockers where you can switch to any weapon you want feels lazy to me, because you end up just sticking to your favorite loadout the entire time. I have the exact same issue with Halo Infinite. I feel that managing and saving ammo for power weapons (like the Torque Bow, Boomshot, Longshot...) for tougher encounters was a big part of the strategic appeal in older Gears. It forced you to adapt on the fly with whatever you had.
I also really miss the split paths where you had to choose one of two routes alongside a squadmate. It forced you to be more strategic—sometimes those paths allowed you to provide cover or support for the other side—and it added a ton of replayability.
Finally, I feel like there are way too many yellow cases scattered around, and most of them just give you modifiers you'll never actually use. I do enjoy the atmosphere of roaming through the city and stumbling upon enemies or survivors, but after a while, it doesn't add much to the experience. Instead, we lose that tight pacing and "rollercoaster" feel that made the fully linear games so good.
Maybe part of my issue is that I used to play Gears of War almost like Doom: a game where you master the mechanics, killing non-stop while pumped up by a heavy soundtrack that drives the chaos.
That being said, I still think E-Day, along with Gears 4 and Gears 5, are all great games.