Magnetic Island is tiny but totally stunning.
Townsville is the greyhound bus stop and then you get on a short twenty minute ferry over to the island. It is not worth spending much time in Townsville and I would utilise your time exploring magnetic island, its sensible to get a hire car between friends.
The Base hostel was also one of my favourites and well worth its price tag!
We hired a car and ticked off a lot of what the island has to offer in one day: Horseshoe Bay, Arcadia Bay, Nelly Bay, Picnic Bay and West Point.
We fed rock wallabies (tip- they LOVE the leafy celery sticks).
The island has some incredible walks, beaches and history.