I played your list tonight with a different sideboard. The main-deck I swapped 1 mountain for 1 gemstone caverns, and I cut another mountain to make it 60 cards MB. The sideboard i ran 2 Pyrokinesis, 2 Fiery Confluence, 1 Volcanic Fallout, 2 Pithing Needle, 4 Trinisphere, 1 Pia and Kiran Nalaar, 1 Quicksmith Rebel, 2 Boil. I went 3-1 beating Jund, Eldrazi, Storm and losing to Elves.
For the future, I'll likely try this sideboard:
4 Trinisphere
4 Leyline of the Void
2 Pyrokinesis
2 Fiery Confluence
1 Volcanic Fallout
1 Confusion in the Ranks
1 Stranglehold
The Stranglehold will help against Elves, disabling their ability to search for rec sag. It's probably also good in other matches, as it completely turns of fetchlands if they aren't mountains. Confusion in the Ranks is for Show N Tell.
Also, curiously, this deck just won a fairly large Modern event. It's very similar to the legacy version of the deck:
https://www.mtggoldfish.com/deck/668641