I've recently done this itinerary for my friend's birthday with a group of 12 persons, some who knew Thailand very well, and some for whom it was the first time, some with big budget, and some with smaller budget, and at the end, everybody loved the 2 weeks holidays between Bangkok and Phuket, so I decided to share it with you.
Check my personalized itinerary service if you want a fully detailed itinerary based on your dates, budget and interests. I'll include hotels for you, restaurants, bars, transportation, best spots, all tailor-made!