If you want to continue with the medical style of drama, the first one which springs to mind for me is 'Doctor Stranger'.

This drama will keep the theme of the medical side but it opens up a good factor of different things that we can expect in a drama series. The acting - as like in Doctors - is second to none and the entire plot keeps you pulled in.

It also keeps the side of mystery and the past - which is for the viewer - to unravel!