Questioning piecemeal insurance vs one plan

[SDCB432]

Have a Celebrity cruise booked for Oct 2023 and we purchased their Cruise care with the thought we would add flights through the cruise line later.  (Assuming the flight would also be covered as well??)

Now I’m questioning whether I should purchase the flights through them. If we go on our own would it make more sense to buy one outside policy that covers everything or keep the Cruise care and a separate one for the flights? We never purchase for medical - all set there….for now.