@Marni83, u need to update after u have been 🙂
Other food places on Hayling are the Ferry Inn (outside seating with view towards Portsmouth in the distance) and Inn on the Beach (not been to that one). Yes, also been to the Drift and it was nice and friendly.
There is a popular pub called the Ship as u approach the bridge.
If u are after sightseeing then yes, Portsmouth definitely has loads of naval history . U can go on a harbour tour and see some modern navy ships if they are in.
There is also the Mary Rose, the Victory and the Warrior, could easily spend a day there and I think they do a day ticket for the lot.
There are some cannons on the fortress u can climb over for a photo when u get nearer Portsmouth along the beach. Southsea castle is/was free and has a cafe.
Prob not worth going to the aquarium unless weather not good as there is loads to do outside, inc the beach, the boating lake, the miniature village etc, all along the promenade so u don't need to go into the town apart from Gunwharf quays.