First of all, this map is incredible. It looks like an actual remaster that Treyarch would make for black ops 3 and the atmosphere is perfect, you nailed it!

But onto the suggestions:

1. Ammo
So I'm not sure if it's just bad RNG for me and my friend, but we ran out of ammo so often and didn't get max ammo's a lot. But, this might tie into my next one

2. Rounds are too long
Zombies don't seem to come into the map too often, rounds take a lot longer than usual, which might be why max ammo's don't show up as often.

It also might be because of normal mode, and if so, normal seems to be a bit too easy.

These are all my suggestions for now, great map though! Keep up the amazing work.