Did my best to fix it, I feel like it now really pushes for the melee kills at the start.
Link to the new level here. And I replaced the link in the OP
Note: when I was initially testing this, enemies would only aggro based on line of sight. The fact that they aggro to gunshots makes the beginning significantly more difficult, but still just barely possible.
My first ever custom level. A bit tricky at first but once you get it down, very doable.
Link to level here