Really enjoyed reading your last trip, so looking at your route i guess it is a "see as much as you can" so i have couple of ideas around my area that may seem odd until you get there, you do like taking photos right

Christchurch the Priory is a must, you will need to park up and take a walk but if you have time to take a wander inside i would do it. Mudeford Quay is also worth a drive to, will be deserted that time of year and very scenic.
Boscombe and Bournemouth i personally do not have a great love for, but the Winter Gardens are nice to have a stroll through on a nice day.
Poole is my home so yes a trip down the Quay to see the Old Town with its history i would advise is a must

Scaplens Court, the Old Guildhall and the Museum all within a 5 minute walk from Harless Chippy and the King Charles pub has to be worth a visit

If you like your Military History the Bovington Tank Museum is awesome, and 10 minutes from there is Monkey World, a proper place where primates from around the world are cared for and given the space and enviroment to live as close to the wild as possible.
When you get to Portland go and take a trip to the Young Offenders B&B, can give exact details but the public road goes round and you get terrific views across the bay, truly amazing.
Yes you will probably go through Corfe Castle but take the B3069 towards Kingston at the end of the village to find the best place to take a snap of the Castle, oh and there is the Swanage steam railway.
But the one place i totally recommend you visit, getting there is a cracking drive with stunning views, but Tyneham Village is not unique, there is another that is not open to visitors in the area, but it is well worth the hour it may take to wander around it, you will need to check when it is open to visitors as it is in the middle of the Army firing Ranges, check it out on google and wiki

Colin
*** EDIT***
Mick just checked the opening dates in November for Tyneham open only weekends but NOT 14th and 15th.