Seems a bit ambitious to me to do all three. I'm guessing you realize that it is 5000 km from Capetown to the Seychelles. I have been to all three and although things may have changed from 3 years ago, I recall there was no non stop flight from CPT to SEZ....(as I looked into doing this). so you are looking at a whole day spent travelling from one to the other. IMHO you could easily spend 2 weeks in the Seychelles (went to Mahe, Praslin and La Digue) . I also did a 3 day stopover in Dubai. Frankly I would never go back. I suppose if you like high end shopping malls that you can find anywhere in the world it's ok. Beaches in Seychelles are nicer than Dubai. Anyways to each their own... 2 of the 3 seems more reasonable given the time frame. Capetown is wonderful and frankly so are many parts of South Africa- deserves a trip all on its own.