My thoughts on
Thousand-year storm is that its a long-game finisher, but not much else - and there are a lot of draw to compensate for fast casting. You're probably right tho, but it requires playtesting.
Risk factor are a side option to change with
hypothesizzle - to counter
steel leaf champion, you need a 4-dmg removal, and monogreen stompy can ignore 4 dmg to the face cause of its tempo. They still could be swapped to main to increase the tempo - depends on the opponent.
Board wipe is a very good idea, i didnt think of that - tokens arent really in the current meta...
Fiery cannonade seems like a very good idea.
Also, there simply arent any answers to
carnage tyrant in the current UR standard. Uncounterable hexproof... The only way to kill it is a combat exchange with niv-mizzet. I really dont want to make that deck a 3-color.