Moonlight Benjamin, Minyo Crusaders and Volosi are all quality entertainment. If you also like the really traditional folk you can also go for Xurxo Fernandes, Lalala Napoli or Rodopi Ensemble. Los Orangutanes looks promising too. But I'm also very curious about the late night acts that are slightly more electronic such as Zar Electrick, Balaphonik Sound System and Zorg & Zoord.