Here's a real quick post of some of my thoughts concerning Storm and what new cards I've been trying.
Kolaghan's Command
This is the perfect upgrade to Rushing River in a deck that wants to deal with hatebear and artifact combinations. Rushing River is clearly more versatile in terms of what permanents it can remove, but Kolaghan's Command is more versatile in the types of other applications the card can be useful for. I haven't played too many games with it, but the writing is kind of all over the wall. Anyway, Rushing River is always a (-1) card advantage, while Command is always a (+1), allowing Storm to play more of an attrition game if its pilot chooses. Though I would still have a Rushing River in the sideboard so that any complicated board state can always be solved.
Pack Rat
I had been operating under my own generalization that 1 Pack Rat in the board is all I'll ever need, however, I've been so continuously impressed with this card to the point of playing 1 Pack Rat in the maindeck and 2 in the board. It's really great against any Thorn of Amethyst deck (Really any creature is), but Pack Rat just meshes really well with the Storm shell due to all the mana and card draw available. It ends games quickly and often the opponent just doesn't have an answer for it.
Plague Spitter
It's no secret now that Thrashing Wumpus has been a powerhouse in the sideboard of Storm decks. Mostly because of the Pestilence ability but also because of the 3/3 body. In advocation for Plague Spitter, the 3/3 body isn't worth the Dark Ritual you need to cast the Wumpus. Getting to 5 mana is too vulnerable to disruption. The only relevant and commonly played hate-bear that isn't killed by Plague Spitter is Ethersworn Cannonist. (Unless they want to attack into the Spitter) This brings up another aspect of Plague Spitter's ability that can actually close out games: Your Ancient-Tomb-Tapping or Cannonist-playing opponent may not be able to afford a stalemate board position because both players will be taking 1 damage per turn.
Thrashing Wumpus had also been an incredible asset for defeating Grixis Therapy decks. Pre-board, the Grixis Therapy player should win almost every time, but post-board the odds are heavily on the side of the Wumpus. Plague Spitter is just a strict upgrade to Wumpus in this scenario.
City of Solitude
I thought this card was amazing when Steve first started to talk about it, but now that I've played with it for a few events, I feel comfortable leaving green out of my deck for the time being. Its a great card but the mana cost is not great, I don't believe its extremely impressive most of the time; although it can be really great about 10% of the time. The opportunity cost is too high for only a slight upgrade to Defense Grid. Play Wheel of Fortune. (and Kolaghan's Command and basic lands)
Eldrazi
This deck is no challenge for Storm. Its less prison (than 2015 Shops) and more vanilla beatsticks instead. A few Hurkyl's, a Kolaghan's Comman, a Rushing River, some Pack Rats, and some Plague Spitters deal with this deck quite easily. The Eldrazi deck's best common play against Storm is turn 1 Thorn of Amethyst; 1 Thorn is simple to defeat. If they continue to compound the Thorns with more Thorns, Thalias, or Metamorphs, then just go for Pack Rat. If they don't compound the Thorns, then they are most likely going for beatdown. In this scenario, just deal with 1 Thorn and then combo off.