Loved Lefkas! Went last year and would have gone this year but couldn't fit flights in because of work committments, so going to Corfu instead!
Stayed in Nidri , at quiet accommodation away from the main bits. Georgeous scenery and good selection of tavernas, bars, shops etc for the evenings.
Hiring a car is highly recommended as Nidri beach is ok but as mentioned, the beaches on the West Coast are better. Roads weren't too busy but typically Greek in places!
Also hired a little boat for a few hours which was fun!
To summarize, I'd say Nidri was relaxing, picturesque, and a good all round resort if you're looking for something a bit different!