I'd send Chartrand and Seguin also.ditto. can seguin do double duty though, as she'll likely be assigned in pairs (pending the success of the pairs FS)
She has been doing double duty at JGP events, and doing it well. I think she could handle junior worlds in two events with no problem.
However, here's another consideration: IMO placement in Junior Worlds is far more important in the women's event than in pairs. It's really important for Canada to maximize the number of women's spots on the JGP next season, because there are a lot of potentially worthy candidates for JGP assignments. In pairs, on the other hand, there are very few age-eligible teams that would do well on the JGP, so placement in pairs isn't all that important (except for personal satisfaction for Seguin/Bilodeau). I think that Canada needs a backstop to Chartrand, just in case she doesn't skate well, and Julianne is the strongest candidate for that IMO.