For short and medium haul routes, you need to sacrifice fleet utilization for the load factor because the penalty is too large. With your route image, you would likely see 80% or more LF immediately with better flight times.
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For ranges below 1500NM(varies depending planes), simply don't fly at night. For ranges above, you can make one leg during the night, and back during the day - preferably to the East for the "red eyes" part. For example, in GW3, I currently have a E145 that flies EGPH-UUEE from 2315 to 0610 (back0700 to 0820). Profitable & full. Just, not all routes are so sweet, and, in some british airports, late slots can be all taken...