Why not dump the negative geared property and buy a positively geared property? Did you fix at high rates? - Just realised I don't pay PM fees for WA properties anymore so my calc's don't include PM Fees so what's positive for me may not be for others. Are you sure you can't do better though?
I read the whole thing and maybe I'm thick but I'm not sure how you want to reduce all this debt in 10 years being negatively geared and on an "average" salary?
My understanding of "how to do it" is:
growth phase - you grow your portfolio for a while, take on the leverage
debt reduction phase - as the name says, pay back as mucha s you can, if need sell some to reduce debt
nirvana - be at a stage where you can either redraw loans in line with capital growth or live off positive cash flow
I don't see how you want to get from 1 to 3 in only 10 years.