My thoughts are only if you tee them off in 6mm cable, which gets expensive. The fuse/circuit breaker is there to protect the wire, and while I can't recall anything specific in the regs about breaking to a smaller gauge, it's not something I like the idea of.
Personally, I'd put a subboard in with a few 16 amp breakers for power (with maybe a 15 amp powerpoint too) and a 10 amp breaker for lights - that way, if you pop a breaker you don't end up in the dark!
Finished connections in any work should really be tested with a specific low-ohms meter ('resistance tester' on ebay for about $60) as they test for resistance (poor connections or dodgy insulation) at high voltage. Also check that the polarity of all wires is correct (all switching is done on the active - you are not allowed to switch on the neutral) and earth continuity (fault loop impedance).
If you do that testing, you'll be in the right hand side of the bell curve regarding testing simple installs in Australia. (I haven't personally seen a sparky test an add on to an existing circuit, but I only have a sample size of two which is hardly representative, but still.....).
Attached is the check form put out by the SA technical regulator, which gives you an idea of the tests that should be done.