Deck description has also been updated.
I adjusted this deck with the cards I currently have. The sideboard is actually IN my mainboard at the moment to buff the card count above 60 cards. However, the cards in sideboard will make up the sideboard once I acquire the Boros Charm and Simic Charm I need. In addition, a longer step to take to update again would be to aquire shock lands to replace the various guildgates I have in my land pool. Also, the maybeboard is used as a public acquireboard at the moment, and consists of cards that I am searching for to add or swap out in my mainboard.
Explanation:
I love the idea of charms in a sliver deck, and I hadn't thought of them as good defense before. Both Boros Charm and Simic Charm will help keep my slivers up. I plan to put 2 of each in my mainboard, keeping 2 Ranger's Guile in the sideboard for playing against decks such as a red burn deck, which can easily counter a creature deck like this.
I balanced out my land acquiring spells such as Verdant Haven, as I hadn't done this prior to adding the guildgates into the deck. Lay of the Land was an old card used before I had guildgates to fix the wrong color mana problem, and was taken out completely. Chromatic Lantern is still a goal to replace Darksteel Ingot, I just don't have any at the moment.
Some somewhat useless slivers were removed from the deck, including Steelform Sliver. This sliver has saved me in the past but in testing, I draw much more useful cards now that I reduced my card count by taking him out. Progenitor Mimic was also swapped out due to it's slow build up time and higher mana cost. A regular Clone was put in it's place, as I find them still useful to increase your army's usefulness when used on a Predatory Sliver, Megantic Sliver, or an enemy card.