Like I said, I built it out of a Panda Connection shell, and I'd belive your core is stronger (although I'm a huuuuuge fan of Faith's Fetters). That said, I'm not sure how good Sidewinder Sliver is. *Shrug* I'll take your core and start testing as a starting point.
I really dislike Gemstone Mine as a land in a deck like this, since you're extremely mana hungry, and I think you need at least a few bouncelands to help your mana. Also, the 1 Gemstone Caverns seems like it could be randomly good, but you don't have a way to get rid of it like the Compulsive Research decks can.
That's a lot of removal, and I'm really skeptical that you need that much. I'm wondering if you couldn't support something like Rough // Tumble. How good do we expect Pyroclasm effects to be (since you can roll right through it)? I also definitely think you want Persecute main, since it is just soo backbreaking.
I agree that Sidewinder Sliver is the weakest sliver in the deck. His biggest upside is his ability to trade with a grizzly bear on the offensive, and if you've got out a Sedge or Sinew Sliver, you can trade him with a Watchwolf or Elephant. His biggest downside is that he is pretty bad without other slivers to support him; he's the sliver who most breaks the "Don't run bad slivers" rule. That being said, a 1/1 flanker is hardly bad, he's just not amazing. I'm not really sure what would be better than him.
As an aside, it is worth noting that this deck is totally tribal T2 legal.

I think the main issue with the deck is optimization; it may be that ultimately some other sliver (perhaps the 2/2 RB sliver, perhaps something else) would be better. The balance of removal is also important. I don't think 8 slots (12 counting necrotic) is too much, nor do I think the 6 discard is too much; you absolutely need the discard, and the removal is great. I agree that Persecute is a wonderfully back-breaking card, especially if people run janky decks like MBC or MGA.