Didn't see the MOD running yet, but as I saw on the video and readed the code, lemme make some suggestions:
// From the video
1. Spawn more entities on the map, if there's 20 or even 32 players playing, it'll be bad.
2. The sound of the airplane drop hasn't much sense, same of the airdrop. Maybe you'll change?
3. The plane sound too, you could add the misc/plane_drone.wav.
// From the code (some of them is maybe for the next update, as your mod is BETA.
4. Add a code that drop player's items with a command, or even a loot.
5. Duos/squad, as I told to you might be cool
engfunc( EngFunc_WriteCoord, 4000.0 )
You could get back to the GetMaxHeight
, just for optimization.
Hope you'll add more effects sounds, anyway, you did a good job.