If I could go away without my kids it would definitely be Cape Verde - I've never been and I'm desperate to give it a go, but as it's very much a quiet, couply place and I'm a single mum with two teenagers, it's crossed off my shortlist for a few more years yet!
There are some nice quality hotels in certain parts of the Canary Islands - Costa Adeje in Tenerife, Playa Blanca in Lanzarote, Jandia in Fuerteventura... all around 4 hours flight. Have a look in the
Sovereign brochure for ideas - some are very expensive but you may be able to get it cheaper if you book independent.