Well in Dover you have to look for the sublime and then ridiculous
The Marine Hotel has seating for coffee etc. in the sun and fairly peaceful. Lots of overseas visitors to chat to.
The seafood outlet. on the promenade, opposite Granville Gardens. Offers a cracking cup of coffee, for a £1.00.
Further down to the Eastern Arm. Our newly elected Mayor and her jolly helpers, have decent all round offerings. Seating and good views, in the sun. Place is called Pebbles.