You introduced all of the characters very clearly and with some nice detail, but I wonder if you could do it in less of a lump, since the first page is almost all description of the characters and not much else. It's interesting description and a page isn't a huge amount of time, but I sitll wonder if it would be worth it to try and sc atter some of those descriptions you've got throughout the rest of the text. They look like the sorts of details that wouldn't be too hard to move along.
The beginning of the story seemed to be a bit of a hurdle to get over, in that you were dropping a lot ofreferences, either technical ones or historical ones, that I didn't really know about or understand. I'm kind of letting the Philidelphia reference slide because it seemed like it was a piece of history that might come later, but perhaps even some of the conversation around that could be cleared up some. What does "wiping" mean in that context, for example? Escobar talks about Jax being a "tp whore" but I'm guessing it doesn't have a whole lot to do with actual toilet paper.
It might not hurt to throw in explanations or at least hints of some of the other story-specific terms you're using. Certainly you don't need to explain all of them, but it feels like a lot is going on that I don't know.
I don't have too much too say about this so far, so onto your questions...
Is there enough here for a viable story? Sure.
Can you finish it in another ten pages? It's kind of a fallacy to answer this, since I have no idea where you want the story to go from here, but... Probably not.
How to make the emotion-deadening thing work: Well, one thing you could focus on is the
intellectual reaction to the lack of emotion (or the altered emotions, at least, which seems more accurate to your story). Given that most of the emotion altering/deadening seems to take place during high-adrenaline situations, though, that might not be too relevant.
That's another thing you can do, is keep the deadhead scenes as high in adrenalin and tension as you can. The absurdity of this guy giggling and cheerful as he runs through a scene of carnage is a good image to hold onto as well.
But mostly I imagine you'll want to be focused on what happens
after the cocktail wears off. There should be some pretty heavy ramifications for that, and part of the draw as we go through the story should be wondering how he'll deal with whatever happens, whatever he's done, and whatever he does or doesn't feel, afterwards.
I don't have much in the way of suggestions for where this is going from here; I don't really feel that there's enough yet for me to try drawing it forward. (Which is why I said that I don't think you can wrap this up in another ten pages.)
Here's a thought which may or may not work for you (with what you've given us so far, I'm not sure whether I would end up using it if I were writing this):is it possible to develop a dependency on the deadhead cocktail?
Again, just a thought. I think that someone could do a lot with that idea, but I don't know if it's for you.
Oh, and do any of the emotions that Escobar's messing around with ever come into conflict with one another? Do they ever somehow conflict with the sense of duty that the arbiters won't let him mess with?
That said, some responses to what others have said...
I agree with Ryos's list. Motives for the perps, if nothing else, will let us know what's at stake, and therefore raise the tension. It'd tell us a little more about your world, too, and that wouldn't hurt either. We need to see Happy go a little nuts. And we absolutely need to see what happens when the cocktail wears off. From what you'd given us so far I'm thinking that that's what the story is
about.
It's really hard to say without knowing what happens between here and the end, and more importantly without seeing the execution of the thing, but I'm not sure I'd be satisfied with Happy dying at the end. Seems a bit like an easy way out.
Okay, I must be stupid. I TOTALLY missed that Jax was talking about wiping his memory there. One more reason to never trust me as a beta reader. Sigh.
Thought: Just because you could very easily draw some of these ideas and/or characters out and use them in a novel does not mean that this particular story has to be a novel. Personally, I don't think I've seen enough of this piece to make that kind of judgement. Cynic, obviously, may have a better idea.