This feels like a good place to repeat my suggestion from another thread on how sligs could behave with smooth scrolling
If the camera is panning, with Abe being (presumably) fixed in the centre of the screen, then think about where that slig would have to be- right at the edge of the viewable area, to the point where it is close to going off screen.
With the flick screen system, if we walked into a new screen to see a slig shouting 'FREEZE!', we had to turn and run straight away or be shot. Also think how, if you stopped running whilst being chased, the slig had to stop to shoot- they couldn't run and gun. In fact, if you were quick, you could stop briefly then carry on running, and the slig would do the same
Point is, the slig needs to stop to shoot you. He will only stop if you do, in which case you'd be shot anyway just like in the classic games. But if he tries to shoot while you are running, he will disappear off screen- and just like AO/AE, you can't be shot from off screen! This way, the slig can try to catch up (for example if you stop and eventually he enters the screen), or it might go back to sleep, revert back to it's original location, etc. Just a thought- it doesn't seem too different to the original's mechanics actually! The only ways a slig would appear in the middle of the screen would be if you dropped next to one from a ledge, or woke one up whilst sneaking- either way, you'd be shot just like in the original game.
Secondly, I feel an important aspect of the gameplay in AO and AE was that it was frantic and tense. All in all, I think it comes down to risk- in Munch, there was a health bar, meaning Abe could take multiple hits from enemies. With this, the risk of approaching an enemy is reduced and the player is not afraid of the enemy since they know the odds of survival are good.
The key to immersing a player in a game is to effectively place the emotion of the protagonist on the player. I think the back of the AO box said it best with 'In a world where everything wants to eat you, you're the skinny guy with no weapons'- I want to feel scared playing as Abe, to feel desperately outmatched just as somebody would in that situation. One hit kills are a must! Running away from a slig/scrab needs to feel like a life and death situation.
On an extra note, I don't know if anyone has suggested this before, but it would be great if Abe's grenades had some physical effect on the machinery when they explode- the level would function in the same way afterwards, but maybe there would be some damage to the metal, a charred patch and sparks from grinders, etc?
Apologies for the long post!