A problem I have is when playing as a Predator or Alien in large dynamic battles is that you basically engage in 1v1 after 1v1. This is why Marines top the charts in Species Team Deathmatch, they can easily engage three or four targets at a time and bring them down quickly. Ranged Predators don't have this problem as much but they are no where near the Marine's level.
Map: Refinery
Game Mode: Species Team Deathmatch
Aliens: 6
Marines: 2
Predators: 4
I was playing as a Predator and only using my wristblades. If two Aliens came at me at once I was screwed. If I was fighting one and another one came at me, I was screwed. It felt very awkward not being able to quickly engage one after the other.
Maybe if heavy attacks had stun splash. Blocks are fine, they block all light attacks that come at you. Light attacks could have small splash damage. Or perhaps even trophy or stealth kills could stun nearby players for one second really close to the player being grabbed.
You might say, "Stick together in a pack." Well, yeah this is a good tactic but it really limits the potential for epic encounters (a factor this game severely lacks).
/ramble