I will look at all direct options before any routing with a transfer, regardless of carrier (within reason, of course - FR is not an option but usually everything else is). If a transfer is inevitable, I would probably look to be within 10-15% of the cheapest price available for the routing to stick with a preferred airline/alliance.

Being based out of MAN, where the likelihood of connections versus those in the south is higher, I prefer to go direct where ever I possibly can.