a sliver deck i am in the process of building, i'm trying to go for a more competitive route for this deck. please let me know what you guys think of this and what i could do to improve it.

currently galerider sliver + prophet of kruphix/ thorncaster sliver + bow of nylea/ essence sliver + bonescythe sliver are the combinations of cards that will be side decked for each other, below are just notes to myself about mana for the combinations.

galerider/prophet = 5 forest, 8 mountain, 7 plains, 2 temple of mystery, 2 temple of enlightenment

thorncaster/bow = 7 forest, 8 mountain, 9 plains

essence/bonescythe = 5 forest, 7 mountain, 12 plains