The deck isn't well optimized.
Shimmering Tempest is bad compared to Kabal Chemist. If you've played any Freeze Mage at all, you'll know that its turn 4 is one of its weakest. Getting a minion to play for board and a potion is huge and helps the deck curve out well.
Also, the deck as is can't beat armor or taunt. I added Burgly Bully and Antonidas for some alternative win conditions (remember cheap spells from Primordial and 1 Mana Bind). Molten Reflection kinda sucks too. Much better to run a single Molten. By the time this deck is ready to win it won't have any health so the Molten might even be more reliable than the Arcane Giants.
No spell burn so Bloodmage is expendable and Poly doesn't seem worth the slot/can be gotten from the random spells generated.
Changes in full:
-2 Shimmering Tempest
-1 Bloodmage Thalnos
-1 Polymorph
-1 Cabalists Tome
-1 Molten Reflection
+2 Kabal Chemist
+1 Burgly Bully
+1 Archmage Antonidas
+1 Mana Bind
+1 Molten Giant
6
Lol, I don't play Rogue, personally... But I feel the memes were right.
2
It may be worth noting that on turn 8 you could use Kabal Lackey as a one mana spell for the purpose of Archmage Antonidas.
Archmage Antonidas > Kabal Lackey > Counterspell for example.