Okay. I will TRY to please every type of fan (hardcore and casual/legacy and conviction fans)
Let me start off with the gameplay itself. I will list all the features there are but keep in mind, different modes will have some of the features deactivated or activated while others won't. The different modes are as follows:
First off, mark & execute and LKP return! I hear you classic fans cry. Mark and Execute would be changed to allow for slightly more involvement and input from the player. Mainly, now it allows you to select a max of 3 enemies (and you must take out 3 enemies first, 1 mark for 1 SILENT takedown and only a max of 3). You dont get instant headshots instead it snaps you to the closest enemy's largest center of mass -- their body-- and you can fill them will holes or move the reticule upward to their head (while in M&E, the X button would cancel the operation and the only way your reticule would move is up and down meaning you will always be targeting the enemy but you still have to go up to their head for a headshot. You could then snap your reticule in either direction (if there is any enemy in that direction) and continue. If there are two enemies in the same direction for the first, it will snap you to the closest but if you want to take the other guy out, you snap it again. Maybe it'd be called Mark and Snap lol -- nah.
LKP can be viewed in two different ways -- with an LKP "ghost" or an LKP "spot". The ghost shows you your last known position including what weapon they saw you with and what you were doing -- this would be used in Casual. The "spot" is just a spot giving you the area in which you were noticed -- this would be used in Veteran. The other difficulties have LKP still active just not visibly so.
Next up: VARIABLE SPEED! Here's how it works -- like the first 4 god dang games! xP But seriously, it was so much more useful even if you were going for a more action oriented experience -- the fast crouch run was so much faster than the speed in SCC and you could also go slow and silent to grab an enemy. It's a no-brainer.
Classic moves: The splitjump would return and have a few more instances where it can be used. After the first one, each game seemed to use it less and less...I remember a few times in PT, fewer in CT and none in DA. It would be as used as the first game but with the animation from CT. You will again be able to whistle by pushing Down. When against a wall or next to a door, you will knock on it. Corner takedowns will make a comeback: both the one where you jab their adams apple and push them to the wall before putting them into a human shield and the one where you grab them and pull them to the floor. Not only this but pushing Y while you have the enemy on the ground will actually pull them to the human shield position (in case you need to move before another guard comes by). RT will now do lethal close attacks (with the SC knife or hand-to-hand krav maga, depending on what you want and choose to equip) and LT will do nonlethal knockouts or krav maga depending on if you equip the knife. this would replace SCC's RT which pulled the gun out and fired.
Center Axis Relock comes back and you can move about a mission with the gun in the ready position like in SCC or not. To actually fire though, you must push the X button like in the past SC games, only now the viewpoint is still the pulled out camera view like in SCC. Pushing the zoom button RS (the thumbstick) will bring it to the close, over-the-shoulder view ffrom the original games. Pushing it again (if it's the SC-20k or another scoped weapon) will bring it to the scope view and clicking it again, will bring it back out. RB will bring up the inventory like in all the old SC titles and you can cycle through what you want. Medkits return and are the PT iteration -- that is you bandage your wound as opposed to drinking medicine.
The SC-20k comes back with all it's old gadgets as well as new ones: sticky cams, sticky shockers, ring airfoil rounds, tranquilizers, camera jammers (produce static image -- they replace the OCP device on the pistol by limiting the amount of times you can take a camera down without destroying it). The ultrasonic emitter would replace the OCP on the pistol. You would be able to pick up any weapon and the PEC would return (choosing the SC-3000 is lighter and would allow for slightly faster movement but all gadgets would have to be thrown, limiting how far they can go. The laser mic makes a return
And because I'm tired...I'll post again later. Night/Morning everyone!