People don't realize this but the Sage was basically a small fragment of himself that transcended through time.
He was in no shape or form close to his full power.
To make an estimate which would appease to most people. I'd say the sage in his spectral form was no more than 20% of his max power.
However with that 20%.....
**Powered up Naruto and Sasuke tremendously
**He created another Massive CT and sealed Kaguya
**Rinne Tensei EVERY KAGE EVER FROM THE PAST! WITHOUT them having bodies
**Undone SOMEONE elses Edo Tensei
**This is also after having enough chakra to SURVIVE 100+ Years through multiple people
These feats a lone are superior to any other shinobi in the series in terms of 1 single person doing it.
He was in no shape or form close to his full power.
To make an estimate which would appease to most people. I'd say the sage in his spectral form was no more than 20% of his max power.
However with that 20%.....
**Powered up Naruto and Sasuke tremendously
**He created another Massive CT and sealed Kaguya
**Rinne Tensei EVERY KAGE EVER FROM THE PAST! WITHOUT them having bodies
**Undone SOMEONE elses Edo Tensei
**This is also after having enough chakra to SURVIVE 100+ Years through multiple people
These feats a lone are superior to any other shinobi in the series in terms of 1 single person doing it.