Rod Heikell's pilot to the Ionian is regarded as the dog's bolleaux, published Imray. The currents are not strong and the tide negligible. Great area, but a but light on the wind front. You'll like it.
Imray also publish the much fatter Greek Waters pilot (also by Rod Heikell) that covers all the Greek waters, both the Ionian and the Aegean. It's pricier, but might be worth considering if you ever fancy chartering in the Cyclades - absolutely great area IMO - more wind and greater distances between anchorages.
Both are very clear and well written - as you'd expect from Heikell.