Downloaded, I'll walk through what I found.
Got to the beach, all the statics have the same rotation, rotate the around so it doesn't feel as mechanical.
Sandbags are clipping through the wall.
You have a lot of terrain clipping through objects throughout your whole level.
It way to barren out there, Hadley any cover or concealment, and logs, sandbags, hedgehogs, smoke in craters, dust effect, anything.
Ammo crate bundle clipping at German camp.
I know there are 2 other types of wall in this group, use them so it doesn't look so repeated, also add angles. Your house is on a slope, so build the walls around that slope, not through the slope.
The house also has literally one object in it, I'm not sure if that was they only one you were going to put in there or if you are going back to it later.
Go into your overgrowth, in your "tree1" material the subgroups ie (tree1,dead1,dead2,dead3, etc.) have individual values, set the "normal scale" from "1" to "0" this puts your trees all facing up as trees like to grow.
Set your "detail texture" for your rock to "2" instead of "1" and reload them.
Terrain clipping is also horrible at the bunkers, and needs some smoothing work.
Ambient sounds, with exception to the explosions, I didn't hear a thing, you need to add some.
At quick glance that's all I could really see, I know its a remake but you shouldn't feel like you cant improve on the original.
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