I wasn't sure where I should report this, since I assume it's not a bug but a simple oversight. The aura used for rank 3 of Immolation is still the old fire legacy aura (Fiery Form on the Legacy Aura Vendor), while both rank 1 and 2 of the power use the new aura (I assume it's the Thermal Energy aura from the Drifter Store) which leads me to believe that this was just a detail that was missed.
Here's Immolation at R1 and R2
And here's Immolation at R3
Comments
I take this quote from a review that I agree with.
"customisation is so linear; everyone is after the optimal dps:survivability ratio with 0 reliance on other players = autonomous gameplay... Players don't need each other anymore... which in my opinion is a bad thing."