It was our first cruise ever and we would give it overall mark of 9/10. We were sailing as a family of 4, and had a fantastic time.
Embarkation was easy (took around 30 minutes) but stressful as we were waiting for Covid test results which were fortunately negative. We have also bought a costa insurance which they have indeed checked while scanning our tickets (it showed that I had 200 EUR of onboard credit and the whole family had Costa "Relax" insurance).
The ship is huge and very new - everything was polished and each corner of the ship felt like it was made just few weeks ago. We had a balcony cabin on Deck 15 which was not very huge but it was satisfying to be able to go out in the balcony to enjoy the view with the sound of waves (strangely, the ship did not make any engine/diesel noises as I think it utilizes hybrid engines).