Hey. From playing the Spy task on TTW I've come up with some ideas on how the Predator mode should be changed:
1. Predators should be completely invisible to enemies.
Enemies who have the predator mode bonus aren't completely invisible. Their gosteks only appear with lower opacity, making them almost - but not quite - invisible. This has lead to some players using settings on their screen which makes the game look bad, but allows them to see predators easier.
I don't think it's reasonable that adjusting brightness and gamma to absurd levels should grant you with any advantages in a gamemode which is played on a fairly competetive level. Therefore I think it would be better to make predators completely invisible, as long as their level of health is full.
2. The names of invisible teammates should appear over their gostek's head.
Just like you see names of teammates who are outside your screen, or who you point at with your crosshair, I think it should be possible to see the names and position of teammates who are on the screen but with Predator mode activated.
In teambased games with friendly fire switched on there has to be a way to see the position of predators on your team, so that it's reasonably easy to avoid shooting them and thereby teamkilling. Just avoiding the spray of enemies can be hard as it is and if you receive fire from your own aswell having Predator mode can be a disadvantage rather than being the "bonus" it's supposed to be.
Alternatively predators could be immune to friendly fire, just like flaggers are on some CTF servers, but I think it's more reasonable to just put their name over the head, fully visible to teammates.