Well yes you have to connect through JER but the Dornier is based in GCI, however for many of the routes you mentioned you have to connect through JER. BVA, IOM, BOH and certain BHX, NWI and EXT flights you have to make a stop in JER before going on to your final destination.
What I would like to see with regards flights/ new routes out of Guernsey is the following:
BOH - direct and not via JER
NCL
CWL
LCY
DUB
EMA
LTN
and a Joint JER/GCI-CDG service (preferably operated by Cityjet or Airfrance)
AMS would be good too! Bring back KLM!!