The more practice you get, the faster Lorcana games go
Red getting Impulse draw, often tied to combat damage, is nothing new in MTG at this point
You can move counters onto non-creature permanents only if the movement effect states that you can
Play Booster Display 36 Unidades Foundations
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 tiny opportunity cost means you may not need a heavy defender theme to make Coral Colony viable, but it obviously helps and also provides another way to kill opponents using Axebane Guardian + High Alert untap loops