I don't think that Tool Scrapper will be an easy fit in most of the projected top tier decks. Decks such as Darkrai/Hydreigon, Garchomp/Altaria, Eelektrik variants, Empoleon, Accelgor, etc. are already pretty tight and adding two to three Tool Scrapper may hurt their consistency.
I like Eviolite for the reasons already posted: it can turn a 1HKO into a 2HKO, and a 2HKO into a 3HKO. I agree that your two Virizion should be dropped for two Eviolite.
-2 Virizion
+2 Eviolite
The deck's main strategy is to tank using Hydreigon's Dark Trance ability to move the Energy off of your active attacker (most likely DarkraiEX) and use Max Potion to heal all of the damage done to it. Therefore I would add one Max Potion. To do that I would drop Tool Scrapper down to zero (having only one makes it very hard to get when you need it so it could be entirely dropped to boost consistency elsewhere). I would add a Professor Juniper to increase your draw power, better ensuring that you can get the cards you need.
-2 Tool Scrapper
+1 Max Potion
+1 Professor Juniper
I find that the deck lays cards down fast. You are also discarding a lot via Professor Juniper and Ultra Ball. As a result of this I run Bianca instead of Cheren. I find myself drawing three to six cards very consistently (obviously less consistent as you get closer to the number six, but you're still drawing the same or more as you would draw with Cheren). Based on that, I would drop two Cheren and add two Bianca.
-2 Cheren
+2 Bianca
Finally, Sableye is obviously a great fit in this deck. It is an awesome starter because you can begin to set up by playing/discarding Item cards and then placing them back into your hand via Junk Hunt. I would suggest that you drop one (possibly two, but just one for now) Item card and add another Supporter to boost your ability to consistently draw the cards you want. I'm going to say drop a Pokemon Catcher and add a Bianca, however you could just as easily drop a Dark Patch. It really depends on what you find yourself needing more!
-1 Pokemon Catcher
+1 Bianca
I hope that all came out coherently and gives you a couple of ideas for the deck. The changes that I suggested put your deck list closer to mine, and I have been finding a good amount of success with the list I am using!
Ultimately do whatever you find works best for you!
