As someone who has relatives in various parts of Ukraine I might see things a bit differently, when Wizz first announced routes from Kharkiv we were surprised as Kharkov isn't really a tourist destination like Lviv or Kyiv, granted it is a gorgeous city but not one I would visit more than once. From what I have been able to find out from family and friends in Kharkiv the London route is very hit and miss, there have never been any full flights or even 3/4 full flights in either direction, however when I flew Luton to Lviv and return at the end of October / beginning of November both flights where full with no empty seats at all, when I commented to a member of cabin crew she said it was usually like that to Lviv or Kyiv, she said it was very rare if a flight was less than 1/2 full. As I have already said Kharkiv is not a tourist city it's a bit like Mykolayiv not many people have heard about it because it's not a tourist place.