For every person that loved the wasps there were others that hated them, just like the vultures.
UMA zombies were removed for the sake of performance and optimization. It was a good move for this game whether you want to believe it or not.
The larger zombie models (announced and unannounced) were scrapped because the code to make them work with everything else in a fully voxel game was too costly for what you'd get in return. Also a good move for this game.
Zip lines... yeah, well, you got me there. I was voting for feral zip lines.
Anyway, you forgot a few: sharp sticks, crafting grid, fatigue or whatever that was called, gun parts, S&M chambers, etc. If you want it added in either mod it in yourself or go to the mod forums and ask if someone else was planning to do it.