Hi Carol. I went on this holiday last May. It was my first holiday with JustYou and I really enjoyed it. The hotel is glorious, friendly helpful staff, and good food. The rooms are amazing. San Marco is a lovely little place with friendly people but it's only a small village with very limited shopping. Santa Maria the next village/town is bigger with a decent range of shops, banks etc. You can find most things there. There is a bus service there although I never used it as I walked along the beach to it which was wonderful.
In your room you will have a security safe, and a fridge/mini bar. I think all the rooms have balconeys, and they have great views out onto the sea or onto the marina. Breakfast in the morning is buffet style and there really is everything you can think of including bacon and scrambled eggs. The evening meal is waiter served with good choices.
I went in May too and found it cool in the hotel at night as the front lounges don't have windows. My advice is to pack some warmer clothes for then as I found it got a bit chilly. There is plenty of seating inside by the bar though, which incidentally is not a cash bar, you have a card and pay for everything at the end of the week. The tap water is not drinkable so you can get bottled water from the bar, or there is a basic friendly supermarket in the village. We had 2 evenings of live music in the hotel which was nice.
As for the included trips? I enjoyed them on the whole. If you are active you will have no problems, just pack good walking shoes! The only thing I will say is that the area is quite remote so on trips you do tend to spend quite a lot of time on the coach to get anywhere.
If you have any more questions please feel free to ask! We had a very wide range of ages and most everyone managed very well. I have decided yet what I am doing this year, but I am strongly tempted to go back as I loved the place so much. So you never know. We may meet up!