For the original poster, you inspired me to further my idea with the ideas I had for the new Predator game. Thanks, I haven't been posting here in some time due to school. Here's what I've had so far.
Predator: Galactic Jungle
Plot: The story takes place immediately after Alien 3. Bishop from Alien3 has learned of a planet that hasn't been colonized and has Xenomorphs from the original "Mother" system. "Mother" later turned against the company and comes out of the system. Lucretia is still alive fed by blood samples from the Predators killed in Concrete Jungle preserved. She remembers what happened to her almost 2 centuries ago and wants revenge. She also has a psychic sense which she can see things. She notices a Predator ship with the Dark Blade Clan mark. She has Bishop send in Marines and go to this new planet to colonize it so she can find Scarface and kill him for killing her family.
The planet has been used by Predators to hunt Xenomorphs and other species. It seems very unoriginal and similiar to AVP 2 on PC, but CJ was similiar to AVP plot-wise just you didn't fight Predators.
Scarface is now the Elder of the Dark Blade Clan. He leads his clan into the planet to have experienced hunters and unblooded hunt. They see the new colony set up and try to get the humans out, but Scarface and clan mates get captured by Weyland-Yutani. The company sees they can also kill Predators with Xenomorphs.
In comes you, a fresh young hunter after their first kill. You must find and rescue or avenge your clanmates to prove yourself as a Hunter.
It would defintely be rated M for dismemberments, violence and skull ripping.
Definitely multiplayer in this.
One multiplayer game is Hunt the Trophy where Predators compete to get a trophy kill. One with 10 trophies wins the match.
Bonus Missions: Play as a Predator on various planets. The missions would take place from the comics and the movies. Recreate the battle against Dutch with you winning. Hunt in places like NYC and Russia and South America from the comics.
I like the Create a Predator Idea. Like in MK Armageddon, find various pieces of armor, masks and weapons (like the dual shoulder cannon in AVPR) to unlock and make your unique Predator. You can start by making your Predator male or female. Then select color, size, mask, armor and then you can also find in Bonus Tasks the features of the Predators from the movies and comics (Like having the Predator 1 Mask, but in Predator 2 armor).
Training would consist of both moving and using your technology. The fighting aspect would have you against other Predators to learn new moves. There would be weapon training like in CJ. I would make the Plasmacaster sound like the one from the movies.
I was considering subtitles for when Predators speak to one another, but I don't know if it would work.
You have the option of skinning enemies, you can scan a soldier or someone else to see if they're worthy. There are bonus Trophy (Skull Rip) kills which can help you upgrade your skills.
I see weapons being upgraded like Force Powers in Jedi Knight: Jedi Academy. You are given points at how well you hunt and fight. The more points, the more you can use to upgrade your abilities like how much you're healed by a Medicomp, how fast your Wristblades kill and the amount of damage your Plasmacaster does.
Bosses (in story order)
Xenomorph (On planet)
Alien that was the original design for the Predator as a bonus kill (On planet)
5 Colonial Marines
4 Syndicate Mercanaries
Bad Blood (All bosses are fought around the colony except for the Xenomorph and Alien in jungle)
Predalien (You rescue a Predator earlier only it gets chestbursted and the Predalien runs away quick to the Hive)
(She finds the old technology Hunter used to make himself like a Predator and uses it to turn into a Predator and torture a weakened Scarface, she is ready to kill him until you come in) (She also has a room with a shrine of Predator skulls and blood from the Predators she captured and killed recently. She got crazy after remembering what it did to her family, obsessed with them like Rykov from AvP2)
I was even thinking about a mini-game where you do button-mashing to get a Facehugger off your mask if they jump onto to it.
Boy, did I just say a mouthful.