I think suites on big ships are actually much better value than smaller ships , but they do sell out quickly.
P&O website list suite benefits ,
Perks of a Suite include:
A whirpool bath*
Butler service*
Larger dressing area
Priority check-in and boarding (from Southampton)
Daily fresh fruit
Coffee machine
Free room-service
Exclusive restaurants
Bathrobe and slippers
Other exclusive touches
Daily steward service
Telephone
Hair dryer and safe
Tea and coffee facilities
Air conditioning
Vanity writing desk and chair
Beds convertible to twin or king-size bed to suit your needs*
Toiletries from The White Company
Champagne and chocolates on arrival
Canapés on embarkation and Celebration Nights
also see cruise with Amber for a list and good video of one of rear suites , which are to be recommended for bigger balcony. Except for breakfast suites don't have exclusive dining like on many lines, but then price is much less.