hotels in hania

You really need to state your budget in either euros or dollars. "Midrange" does not mean the same thing to everyone. Some people don't bat an eye at spending $500/night for their accomodations. Do you?

We stayed here in 2007 and found it quite adequate. It is very central and idieal for walking.
http://www.kriti-hotel.gr/

For midrange, I would take a look at recommendations in Let's Go or Lonely Planet. Most of the places we stayed in Greece from these books were acceptable.