Our family summer holidays have been to Mallorca for the last 3 years, last year with Shark and his tribe. (Shoal? Curious about the correct collective noun for sharks, I just googled it and it turns out that 'shiver' is one option. Lovely.) The first two years we stayed in Cala D'Or. If you are on your own then Shark is right, Barques is best. Great routes, always other climbers around, and while the cave is often humid I've always had decent conditions on the Metrosexual section, even in the middle of summer. No bolts at the top but you don't need them. The beach is lovely for family, too. Diablo is not a good idea if you're on your own and I've only ever seen one other climber there on my visits. Porto Colom is excellent and there are usually other climbers there. When are you going?