We've got exactly 240 base ICPR before Fate, which I moved to a more conspicuous, intuitive location on the spreadsheet.
I like the idea of trying to derive a rough target for ICPR. Screwing around a bit more, I got a rough number for how much I burn in a minute, and it falls within your 5500-6000 Power used per minute range, unmodified by power restores. I was on the lower end, using a 1hander, with power legacies. So say -5750 PPM.
Can't expect ICPR to account for all that, lets look at other things that give power. You included some of these in your number, but I wanna lay each one out there: So if 1 RC/min is roughly 500 PPM to me, 0.5 Pot/min is roughly 712.5 PPM. Food is what, 600 ICPR which is already in units of PPM? That leaves me with -3938ish PPM to account for somewhere? I acknowledge the existance of blue CJs, but I dunno how to account for them. More rally cries would help, less would hurt, but if there were just 1 per minute, 2500 ICPR from stat there oughta make the tank in question good for like 3ish minutes. (Numbers are getting rougher the further down this rabbit hole I go. Start with rough numbers, end with rough numbers.)
I guess a lot of it depends on how much power help you can count on from other sources, like food & stuff.
In other news, been trying to fix little problems with the spreadsheet. Earring of Defiant and Trev Gallorg had their stats swapped for some damn reason. Added in that will no longer changes power, added in new Crit D formula, somehow I had the equip stat for banner of hope off by like 7 morale, changed Hytbold and Moors armor stats to include the fate for ICPR changes RockX made. Still digging around for tiny things that mayve escaped my notice.