Hey !
Maybe it's worth to look for cards like
Abbot of Keral keep, Monastery Swiftspears or
Stormchaser Mage, I feel like
Thing in the Ice is kind of too slow for what the deck aim to.
Jeskai Charm is good, if you have some Prowess Creatures to buff, otherwise it's mostly a 4 damages spells with 3 colors,
Boros Charm do it better. Maybe get some
Lightning Bolt, they are actually not that expensive, and will be a great addition. In deck like this, you also don't want to play 4
Path to Exile, it may have no impact for aggro vs aggro match up, but against a Midrange/Control deck it can impact, you don't want to get Wrath 1 turn earlier or see a T3
Siege Rhino,
Vapor Snag is better by a mile.
Also depends if you want to spend some money or not, but the best "combo" for counter spell in Tempo Deck like this, is : 2
Dispel + 4
Remand (those can be "expensive").