If you've got an extra day and are happy navigating without any trails then the Irenabyss round trip is great.
We did it as a group of 6, so we floated our packs across the river on our strapped together thermarests. It was still a very cold swim, but totally worth it to camp in such a beautiful spot.
From there, the next day is some great ridge walking - solid going uphill - but unfortunately we ended up camping on a soggy tussock covered hillside that was infested with massive leeches.
The last day is more great ridge walking except we couldn't see any of it in the whiteout (in January!) and needed some serious map-and-compass work. The jeep track out is meant to be easy, but we unwisely tried to cut down a ridge to the road and ended up slogging through dense scrub then forest.