Good day! The whole of Greece is gorgeous but since Corfu and Rhodes are different I would say everything depends on what you are considering. Corfu is very green and washed by the Ionian Sea. Rhodes is also green, it is washed by the Aegean and also the Mediterranean Sea - the Mediterranean is warmer and calmer

If Corfu - look at the regions of Dassia, Perama, Benitses If Rhodes - see the regions of Kallithea, Faliraki