Opinion on RTW ticket price and possible alternatives

Hi all,

I am looking at doing a 3 month trip starting from the end of September and getting back home for Xmas.

The rough plan is as follows:

Flight 1 : Dublin - Jakarta (3 weeks in Indonesia)
Flight 2 : Jakarta - Perth / Darwin (1 week)
Make own way to Red Center (2 weeks)
Make own way to Sydney (1 week)
Flight 3 : Sydney - South/North Island NZ (not sure yet)
Make own way down through NZ (4/5 weeks)
Flight 4 : South/North Island NZ - Dublin

I have a quote of about 2900 USD for this combination roughly (this doesn't include the flights I need to take to cross Oz).

What do people think of this price (with AirTreks) and can you recommend any alternatives I should look up for estimates. I am going to try Trailfinders aswell but I hear they can sometimes be pricey.

Thanks in advance