For me , who is not really a "Romantic" you understand......
1. You need the sea view
(Obviously there are many places without this perk but you will visit those during your stay)
2. You may want a different Mediterranean choice of meals that maybe move away from the usual enjoyable Greek cuisine.
3. You may want to lay on a special surprise and book the table plus "Your Surprise" during the day.
So.... unusual for me to give any tips , but , in this case try "Costas on the Beach"
Go and see Spiros first, book a table, and if , for example you have a specific bottle of wine, maybe all the way from the UK, or any other specials in mind, then just ask if Spiros will do the necessary.
Tell Spiros that Negg says he will look after you.
But... anywhere in Arillas , regardless of view and choice of cuisine, will welcome what ever personal celebrations you have in mind and will look after you well.
Negg ( And I am not a romantic!! )