If easyJet took on any of the bmi regional German routes they would almost certainly only be daily at best, although fares would probably be cheaper in general than BM.
bmi regional is increasing its frequencies to multi daily and, vitally, offers LH code share connectivity via FRA and MUC which easyJet would not be able to do being a point to point airline.
Jersey was rumoured as a possible easyJet route a few months ago. Again it would probably be daily at best and less than that, if anything at all, in winter. Blue Islands provides a 2 x daily JER service right through the year.
Whilst easyJet brings a tremendous amount to BRS, and I have used them many times and find them entirely satisfactory as a passenger, I do think that BRS needs a mix of airlines and I'd hate to see the likes of bmi regional and Blue islands disappear from the departure and arrival screens