Oda’s usually very transparent about the strength other of the villain’s underlings.
Baroque Works literally had the strongest underling being called Mr. 1, the second strongest Mr. 2, etc.
Enel’s priests had their strength reflected in the chance of surviving their trials. Ohm, the strongest priest, had a 0% survival rate
CP9 had Doriki
BM’s Sweet Commanders had their strength ranking indicated by their bounties
Kaido’s All Stars had their ranking reflected in their card-themed names. King > Queen > Jack
So it’s very likely imo that the planet order is just straight up telling us the pecking order. Mercury, the first planet, is the strongest, followed by Venus, than Mars, than Jupiter, and lastly Saturn. It’s no coincidence that Mercury is usually drawn in the center, which is usually the position taken by the strongest. It’s also no coincidence that Saturn is going down first. The weakest of the group almost always is the first to fall
Baroque Works literally had the strongest underling being called Mr. 1, the second strongest Mr. 2, etc.
Enel’s priests had their strength reflected in the chance of surviving their trials. Ohm, the strongest priest, had a 0% survival rate
CP9 had Doriki
BM’s Sweet Commanders had their strength ranking indicated by their bounties
Kaido’s All Stars had their ranking reflected in their card-themed names. King > Queen > Jack
So it’s very likely imo that the planet order is just straight up telling us the pecking order. Mercury, the first planet, is the strongest, followed by Venus, than Mars, than Jupiter, and lastly Saturn. It’s no coincidence that Mercury is usually drawn in the center, which is usually the position taken by the strongest. It’s also no coincidence that Saturn is going down first. The weakest of the group almost always is the first to fall