We found it much cheaper to book a family villa than a 2 person villa in April last year (well outside the holidays), all the 1 bed stuff was aimed at honeymooners etc, approx 400 a week, we ended up in a 6-bed villa near puerta pollenca for about 300, 4-bed apartments could have been about 200 a week...
Have you seen the climbers accomodation in Mallorca here and on Rockfax? It's located in the center of the island so you can drive fast all around the island and offers a quiet authentic environment. The palce is aimed at larger groups and works out cheap if you are over 6-7 people.
For DWS, the water will be quite cold from winter, but the weather will be hot, and not many people wettening the rock!
If you wish to know more about the accomodation or climbing options, don't hesitate to email me!