There is a lot of beachfront activity in the summer, I don't know if it starts as early as May.
I stopped Fao at an albergue entering town, it was across the street from a fair restaurant. I might have been happier if I had walked a little father to Esposende, it was busier with more options. I would definitely recommend a rest day in Viana do Castelo, it is worth a trip on the funicular to Santa Lucia and town has some very good restaurants. Vila Praia de Ancora is a popular beach side resort with rows of sidewalk cafes. Caminha is where you catch the ferry to the other side of the Minha River. I caught it on the end of a weekend beer festival and the ferry was not running on Monday because it had operated all weekend long which leads me to beleive it may have a shortened weekend schedule. The town is very nice, so I had a day to find a laudromat and get my stuff cleaned and dried. Baiona is large with a very lively "old town" full of shops and restaurants. I would have visited the Fort but it was raining heavily the day I arrived.