Every line is different. Silversea has formal optional nights. You will see tuxes and gowns. same on seabourn. Regent is resort casual. All lines have dancing to live music but not to be compared to Cunard. no need for a large ballroom with fewer than 1000 guests. Crystal has dance hosts
regent has marvelous tea daily
All have entertainment and interesting lecturers
These lines are not comparable to Cunard
some overlapping elements
many differences
food far superior on lux lines with several specialty restaurants, most with no charge
you choose what elements matter most to you