Hi Soupy,
Your problem won't be ended by someone saying which nation has the best prospects. The whole industry is permanently in ups-and-downs.
Once you have the technical know-how, and experience of maintenance, you must then decide which nation you should aim at. Many countries have different approaches to the same ICAO aim of aviation safety.
Each National Aviation Authority has different regulations and rules for which you must prepare for Licensing Exams.
This goes for NZ/Aus/EASA/FAA/TCCA. Almost all authorities do not easily accept the Licences of others, and some totally ignore previous experience and qualifications, insisting on you passing their standard as a stand-alone item.
It is not like a Check-Flight for an experienced Pilot's Licence conversion.
Maintenance systems for nations are totally a National matter - there are huge differences even within the EASA nations!
My advice is to do all the training where you are, and, when you are experienced and qualified, then look at what you might get from going abroad.
Once deeper into the industry you might have a different view of the availabilities locally.
Best of luck whichever way you go.
Rigga