Best luxury cruise lines for single solo travelers?

Some Criteria important to me but realize not all will be available on a given cruise: affordable single supplement fees, ease of meeting new people and feeling comfortable(ie not feeling like one is on Noah's Ark),shore excursions where singles are welcomed and not made to feel like the odd person out in the group, dining where one can be with the same people every night, fixed dining ,paddle tennis where offered, social activities for solos, etc

Well, the Hanseatic would probably fit your bill (had a very good experience as a solo) but as it is a German speaking boat, it is probably not what you are looking for.

they are taking good care of singles on MS Europa but of course that ship is now completely German. ( no bilingual cruises anymore)