Cargo should be allocated to least fuel-hungry ships on fleet if below cargo capacity

[Bertie690]

In the event multiple cargo-bearing ships with different engine types/quantities are put into 1 fleet, the fuel usage should be calculated under the assumption said cargo is placed into the most fuel efficient ships in the fleet as space allows. This means you don't have to split out your DLL7 privateers into a separate fleet from your TGD LFs lest they count as holding cargo and guzzle all the fleet's fuel away with that 7.5x consumption.
(Yes this is minor QoL enhancement fyi)

[Bertie690]

As an illustration, I have pictured here 2 scenarios involving a QJ5 privateer colonizer being accompanied by a fleet of Settler's Delight mini-colonizer ships with 300 kT of space left (exactly the amount carried by said QJ5 colonizer). If I split the privateer into a separate fleet with no cargo, the total fuel usage drops from ≈8800mG to just under 7900. That is a 12.5% fuel reduction just by swapping which ship the cargo ends up in! (This is only a modest example - for ships with standard engines or different engine counts, the fuel consumption discrepancy would be even greater.)

Merged:
Separate fleets: