I thought I'd have a look at the last month (October) of two of the three remaining Wizz routes.
Sofia carried 3,453 passengers, ave load 191.8, load factor 83.4% on the 230-seat A321
Warsaw Chopin carried 2,869 passengers, ave load 159.4, load factor 88.5% on the 180-seat A320
Incidentally, Ryanair carried 6,394 passengers on its Warsaw Modlin route, ave load 177.6, load factor 94% on the 189-seat B738
Wizz's Katowice route is remaining (so far anyway) and in October carried 3,286 passengers, ave load 165.9, load factor 92.2% on the 180-seat A320.
It's a shame to lose Sofia - it looks as though BRS will be left with the ski season charter flights. Perhaps Ryanair or easyJet will have a look at it. Ryanair's Bucharest route started a year ago and seems to be doing quite well load factor-wise with, in the period from May to October, respective monthly load factors 91%, 95%, 97%, 96%, 97%, 93%.
Of course, such load factors mean little to Ryanair. BRS has lost routes in the past with similar monthly load factors.