QF is in a period of transition with its fleet, which doesn't happen overnight.
A330's are replacing the 767s
no problems with the dash 8 fleet, one regional turboprop is good
regional jet/717 replacing the 146 and 737-300
737-800 (and possibly 900 and 700 in the future) replacing the 737s and 767-200
744 replacing the SP,742 and 743
A380 replacing (or suplementing being a better word) the 744
so instaead of 146, 737 classics, 767s, 747 classics and 744s (arguably 5 types) you have an RJ, 717, 737NG, A330, 747 and A380 (6 types)
so the only real difference, is one more type at the top end of the fleet.