Okay, so we've finalised everything! Yay! Here is our plan...
22 Jan: Sydney - 14 nights [Family...]
06 Feb: Chiang Mai - 3 nights [Tamarind]
09 Feb: Bangkok - 4 nights [Davis]
13 Feb: Phuket - 10 nights [Burasari]
23 Feb: Bangkok - 2 nights [Davis]
25 Feb: Hong Kong - 7 nights [Family...]
I'm thinking this should give us time to see everything. Decided it might be best to wait till we get to the hotel to book the tours - possibly will email hotel in Chiang Mai prior though.
Many thanks to everyone who has helped me on the forum, you guys are great!