As one who has been involved in this sort of thing in the past,albeit not directly, I can assure all of you that airlines are looking for new city pairs all the time. The two principal drivers are population and economy. Clearly if there is not a large population, (Faroe Islands total population 50,000 - less than Wrexham - with an economy based on fishing and farming), there is .little money at any level in the economy. As ever, we should never rule out international politics when considering new routes. This may explain why Belgrade and Yerevan are not well served currently.
Conversely Guernsey, despite having a population of just 60,000 for example, is well served. Approximately 40% of its economy is based on banking and insurance, together with a liberal tax regime and thus attracts year-round high-spending visitors and not just tourist traffic.