Hi Dido,
I did Costa Brava two years ago and enjoyed the trip (wanted to include xmas and new year).
The hotel was fine and a added bonus for me was that there was some sort of entertainment every night.
Thought a few of the excurrsions were a bit long distance for the amount of time you got there but a few of us got the local train up the coast to make a nice day out, others caught it for extra time in Barcelona (local station was easy walk from hotel).
Weather was pleasant for walking along the beach but you wouldn't be sunbathing, got cool on a night so a fleece or jacket was required if you went out.
Mick