We have HF on our yacht, and have just recently starting using it - Need it for Cat 1 & 2 racing. It is indeed witchcraft - Sometimes fantastic, other times unreliable, but we still have lots to learn.
On the licence front, get the full HF/VHF licence. 3/4 of the course is common to both, so do the extra bit & be covered for both.
Note that most of the radio course is beaurocratic rubbish, rules & regs; I believe ACMA is considering finally moving away from this approach & making the licence more accessible & practical orientated.
Poods