I'm not surprised LGG failed, it was a kamikaze set of routes and frequencies. When you are in reasonable proximity to BRU/CRL/CGN/DUS and others with extensive networks and much lower costs than can be achieved with a F50 you need a sensible offering aiming at convenience.
That is most certainly not Bologna or Venice for starters, the former in particular hardly being a key tourist draw.
I see some logic in Nice, which sees service from just about every French-speaking airport in Europe. 1 or 2 weekly though at the weekend would have sufficed though.
Avignon only sees about 3/4 seasonal pax flights weekly to the UK, I'm not sure there was massive pent up demand from LGG. Again, perhaps weekly on a Saturday may have had a chance.
Perhaps also a Saturday flight to JER, and a ski flight or two in winter.
I'm sure opportunities for niche routes do exist that could be exploited, they just need to be more sensible about it.