hi littlemay,
your itinerary seems very do-able..in fact, 10days is alot to see/do!
i can't advise much on the cradle-mt area 'cos i didn't go there as i had much less days than you do =P you can probably check w adel since she said she's doing very much the same.
i didn't have a fixed itinerary to start with..for self-drive, we usually leave it very fluid 'cos we like to make last min decisions on where to go/stay.
roughly, what we did in the 6days when we were in tassie was as follows:
- arrived at hobart domestic airport late at night..spent one night at Lindisfarne Motor Inn 'cos we were too tired to drive far.
(it was lousy, room was dingy and price was ex)
- next day, we explored lindisfarne, rosny, bellerive (seven mile beach was closed!), richmond, sorell, dunalley (we took the coastal dirt track drive which took awhile but well worth the effort 'cos the coastline is beautiful!), tasman national park (passed eaglehawk neck, taskman blowhole/arch and devils kitchen - must see!), port arthur (where we did guided tour, cruise). then we drove back to hobart and onwards to huon where we spent the night (took us the entire day, quite a lot of driving but still manageable) - pick up the 'Convict Trail' touring map & guide from the visitor's centre, it'll give you clear instructions of the routes and what to see.
- next morning, explored huon region (huon river, tahune forest airwalk). then made our way to hobart (visited apple museum, jam factory along the way, mt wellington *so cold and windy* and spent the afternoon at salamanca *must-see*). spent the night at hobart midcity hotel (good location, decent price)
- next morning, set off to explore east coast (via orford, triabunna, swanport, swansea (consider staying at Waterloo Inn or Swansea Motor Inn with terrific views of bay), nine mile beach (great beach to drive on, pick up some seashells and stop for a picnic, nice view of freycinet national park), popped by freycinet winery (great pinot noir, chardonnay!), down to freycinet national park where we spent a bit more time to explore (i.e. oyster bay, sleepy bay,honeymoon bay, richardsons beach, cape tourville, wineglass bay etc.). then we continued driving to bicheno (blowhole, silver sands resort looks good for a night-stay), elephant pass, st marys and spent the night at Samander (stayed at Chancellor Inn Scamander Beach, decent price w breakfast, great view of beach!).
- next day we continued north via st helens (st helens point, georges bay), pyengana (checked out cheese factory and st columba falls), derby, branxholm, scottsdale (forestry interpretation centre) then to launceston via hwy A3 (16km of long & winding road..quite tiring to drive and scary too). lunch at launceston, checked into penny inn and then explored the gorge by foot for the rest of the afternoon.
- next day, explored launceston city..then drove back to hobart to catch our evening flight to Perth. took the heritage highway via perth (river, eskleigh, baptist tabernacle), longford (brickendon, woolmers), epping, cleveland (stables gallery), campbell (red bridge, museum, wool), ross (sandstone buildings, ross bridge, wool centre), tunbridge (ghost town 'cos everyone was evacuated!), oatlands (court house, callington mill, st paul's catholic church), jericho (convict probation station, memorial), kempton, bagdad, mangalore, pontville.
sorry a bit messy 'cos trying to piece the bits together from memory. we drove the car tires thin..must say it was kinda rush and wished we had more time to spare to explore tassie a bit more. think you'll have a better trip than i do 'cos you'll be able to do it more leisurely and go to more places.
since you are staying the night at port arthur..can do the night tour! 2 nights at freycinet also mean that you can really explore freycinet national park thoroughly - mainly on foot so bring proper shoes/attire that are good for walking/climbing. oh yeah..mosquito repellent too!!