Honestly, I expect by the time you are in the hundreds of hours range or more when you are looking for a job, whether you did it in 40 or 45 or ever 60 will make no difference that I can see.
Also regarding the Navs - not only is there an hours requirement, there is also the requirement of being 150 nm or longer, and with a landing at 2 aerodromes that are not the one you departed from, etc - and yes this can all be done under RAAus. You can then spend the time in a GA aircraft learning the Navaids as happyflyer suggests, rather than the entire lot of hours at the more expensive rate.
CAR 5.84 Private pilot (aeroplane) licence: aeronautical experience required
(1)For the purposes of paragraph 5.77(1)(f), a person’s aeronautical experience must consist of at least 40 hours of flight time as a pilot, being flight time that includes:
(a) at least 5 hours of general flight time as pilot in command; and
(b) at least 5 hours of cross‑country flight time as pilot in command; and
© at least 2 hours of instrument flight time.
(2)The 40 hours must be recognised flight time that was flown in a registered aeroplane, recognised aeroplane, helicopter, gyroplane, glider, power‑assisted sailplane or group A ultralight.
(3)For the purposes of paragraph (1)(b), the flight time must include 1 flight of at least 150 miles, that includes at least 1 full stop landing at, and at least 1 take‑off from, each of 2 or more aerodromes:
(a) that are not the aerodrome from which the flight commenced; and
(b) that are not within the student pilot area limit of the aerodrome from which the flight commenced.
(4)For the purposes of subregulation (3), a landing is a full stop landing if, after landing, the aeroplane’s speed is reduced to taxi speed before take‑off begins.