Harry Mojo you are in for a treat. Its a lovely place.
Not sure about Christmas dinner as we have never been there for that in years. Sure the locals will help. El Marques do a Christmas night evening menu with entertainment.
As you say not burning, but it really is nice enough to get on the beach or by the pool. Arena beach is a a little bit away from where you are staying but if you are fit and able its a lovely coastal walk.
Boats trips from the harbour, just a couple of minutes away from Tamara, well worth the effort. Dolphins etc., beautiful.
Choice of restaurants and bars in LG and beyond in Puerto Santiago and Arena.
Have a fab time and might bump into you, hic hic