Hey, it takes courage to play HRD imo... ;)

You shouldn't really play GU on the phone, the client has lots of bugs that will make you lose games. Can't you use a computer?

If you're looking for a Guild replacement for the Streetslinker, the Shadow Paladin also has hidden, the exact same stats and mana cost. In HRD backline is not much of an issue, since the creatures would always be hidden anyways.

But you're already using 2x Shadow Paladins, so I would strongly recommend replacing the Streetslinker with Pietro, a super strong Legendary.

Also 2x Assassin's Aim and 2x Dark Knives are pretty much mandatory in this kind of deck. Stoneskin Poison is also great to get past frontlines, it's a card that will win you many games.