I don't know what you plan to do about the elevators, but right now they're simply far too easy to exploit. Draw all the specimens toward your position in the top level and then ride the elevator down. Wait for them to slowly walk all the way to the bottom level and then ride it back up. Wait for them to slowly make their way back up top and then ride it back down. You can repeat this tactic forever and you'll never, ever get hurt. I saw someone deliberately doing this yesterday in v2, and if nothing has been changed for v3/v4, then it's still very possible. The elevators honestly don't add much to the level other than an easy way to instantly teamkill, so I wouldn't miss them if they went.