Taking my 7D to New Zealand. Now what lenses?

Hi Everyone...new to the site and looking for a little advice.

I will be heading to New Zealand in a month and want to be sure I have all the lenses that are going to cover everything I am going to be faced with. I will be there for three weeks so my photo opportunities are going to run the gamut. I will be hopefully shooting everything from fern and fauna to large wildlife and tons of landscape. I upgraded from a Canon T2i to a 7D a few months back.

The lenses I have right now are...

EF 100mm f/2.8 USM Macro Autofocus Lens
EF 70-200mm f/2.8L IS II USM Telephoto Zoom Lens
EF 24-105mm f/4L IS USM Autofocus Lens

EF- S 18-135mm f/3.5-5.6 IS Autofocus Lens (received with my 7D body because I was too impatient to wait for the body-only to become available)

And from my much older film camera I have a

EF 35-80mm f/4.5-5.6 II
EF 50mm f/1.8 II Autofocus Lens

I guess my biggest question is for those of you who have shot a lot of wildlife and if the 70-200 with the addition of the 2X converter will be enough to get what I am looking for? Or should I invest or rent a 300mm? I also do not want to carry everything if it is not necessary. Baggage limits are enforced especially on a few of our side trips.

Sorry to be dumb...but I am not sure when I will get back to NZ

Thanks in advance for your patience and advice.