Hervey to Syd--via coastal NSW or New England?

I'm planning to travel from Hervey Bay to Sydney over 4 weeks. I've never been to the Sunshine Coast, have only driven through Brisbane, Gold Coast, New England and parts of NSW North Coast without stopping. So no matter whether I take the coastal or inland NSW route everything's fairly new. The routes I'm considering are:

HB-Sunshine Coast-Brisbane-GC-NSW east coast-Syd
HB-Sunshine Coast-Brisbane-Toowoomba-New England-Tamworth-Syd

Interests are:

• Bushwalking
• Cultural stuff, e.g. museums, attractions
• Not really fussed about being on the beach (yeah I know the irony of being in beach areas)

What is public transport like between and within areas on both routes? The reason I'm asking is, if public transport is difficult in both areas (particularly to bushwalking spots, which I anticipate it would be), then the only thing I would distinguish on is which route would better cater to my interests.

So I guess, on the basis of my interests, ease to get around (by public transport), and availability of cheap or backpacker style accommodation, which route would be better?

Thanks.