Chapter III in particular makes attacking feed you cards, so sometimes Shiva plays out like two turns of Moat. You can also try to combine this with other stun effects to draw extra cards, though there arent many of those (mostly just Ice Flan and Omega, Heartless Evolution)
The good news about the lands in Commander 2017 is that all of the decks get Command Tower (the second most played card in Commander), and all get the new Path of Ancestry as well
To determine that value, look at the nontoken creatures you control and count each one that entered this turn
Sapphire: If you want resources at your disposal, this is the color for you
It's also the cheapest item in the set at $19.99 , so a perfect place to start
The deck might not be bad, it might require some more experience in making these choices