Sorry but scheduled flying at SEN is not a long term viable business.
What a strange thing to say. Scheduled routes to the Med resorts will always be viable from SEN, just as they always have been in the past even when companies such as Air Malta were having to make tech stops on their outbounds. There is a large enough local catchment to support these, regardless of any sweeteners given to EZY or anyone else - I suspect the sweeteners are needed for non-Med routes, with the exception of AMS.
The more important question is whether SEN can attract pax from beyond its immediate catchment and whether overseas pax can see SEN as a London airport. Only that way will the non-Med routes be viable long-term and SEN become profitable.
The comparison with CVT is difficult to understand unless you know nothing of the geography of England.