Just to present a different opinion, I once spoke with a settlement worker who helps people with RQ submissions and citizenship delays. She felt that in some cases, especially if one family member might be subject delays or RQ, that it was best to apply as a family. Her opinion was that the family can create positive pressure for action or processing of the entire file, and that if the files were separate, one or two family members might be effectively "abandoned" in process for years on end, while everyone else sails towards their citizenship. So, instead of the question being whether a member of your family might slow down your individual acquisition of citizenship, the question could be whether you could speed up your whole family's acquisition of citizenship.
It's worth considering.
Also, applicants can usually request to separate their family files in the future if they so desire.
Also, permanent residents have freedom of movement within Canada, so I don't believe that your child going to college in the future in another province would cause problems. And as long as they make sure they continue to meet the residence requirement for PR (2 years out of 5) they can study overseas.
Additionally, depending on the age of your children, it may be wise to apply together since "B2 – A child has made a non-concurrent minor application" was reported as an RQ trigger.