TAFE isn't just an 'easy uni' - it's competency based training (either you know stuff or you don't) and is a good training ground to get you 'skills' - be they trade skills or vocational skills.
There are teacher's aide programs at TAFE but you would have to ask the uni that you want to go to if they will give you any credit (most won't touch a Certificate III).
They also have Cert IV's/Diplomas in Training & Assessment which is what teacher training you need to teach at TAFE (pretty much). Many schools are doing VET integrated courses now (Tourism, Hospitality, VET Info Tech, VET Childcare etc) so having that qualification up your sleeve might a) help you get into uni b) maybe(?) get you a couple of credits for general electives and c) help you when you are ready to start as a secondary teacher if the school does VET related stuff too (the more areas you are qualified in, the more easily employable you are).
See my answer in the other thread about doing Open Uni's though - you could do Literature/Creative Writing/etc with Macq Uni or Griffith Uni (with no entry requirements) then do your Dip Ed afterwards.
