How to launch a character both up and forward

You can either do some geometry with the forward vector (pitch it up, average it with the UP vector, etc) or cheat and just adjust the Z vector you calculate with it (which would have been 0 unless you allow character pitching):

FVector LaunchVector = this->GetActorRotation().Vector() * AerialDodgeDistance;
LaunchVector.Z = 150.f;
LaunchCharacter(LaunchVector, true, true);