Item of Power total cost -1
Staff of Death +2 for being a walking stick sized staff. , Feeding dependency +1 , must use fire to "consume" living flesh
Channeling fire -2 2 focus item slots are used on the staff itself for +1 to Offensive fire power,+1 to Control: Fire
Refinement -2 +2 focus item slots[ for another +2 offensive fire power], +1 Control Fire, +1 Power Fire
Looking it over, this...doesn't quite work. Since you have only Channeling you can't get Refinement except for Item Slots. So, 6 Focus Item Slots total. Which isn't enough for all the bonuses you list (especially when they all need to be assigned to either offense or defense). If you assign 4 to Off. Power and 2 to Off. Control you're good for the Rotes listed...but you need a Focus Item other than the staff since you lack Lore 6. Also his defensive magic'll be at about 3 Shifts.
Alternately (for slightly more brokenness) you could instead get Evocation and have your one Refinement be in Specialization (for a total of +2 Power, +1 Control with Fire) though you'd then only have 2 Focus Item Slots (for +2 Off. Power). That'll still all fit in the staff, and his defense will be at 5 shifts, but his offense will drop from 8 to 7.
In short, you somewhat overstate the magic you can achieve with -1 Refresh even with the drawbacks. 7 shift
defenses? Not with any offense to speak of you don't.