Hi Rachiem,
We have booked with a TA and with Oceania direct, which is very easy, although the TA may give you extra benefits. You can opt out of Oceania’s flights and receive a generous discount with which you can book your own flights, and most times save enough for your Hotel at the destination. Most airlines fly to Barcelona from the UK but as stated earlier I would fly the day before. Also bear in mind that transfers from Rome to the airport are very expensive (circa €150) but easy to book yourself. From the O Life choice we always take the drinks with lunch and dinner then upgrade when on board. You only need 3 drinks outside of the lunch and dinner benefit to be in pocket. I agree with you that Celebrity is getting rather expensive. We have done six cruises with Oceania but never on the smaller ships. Whatever you decide I am sure you will love Oceania. Go for the 10!!