I'd been thinking similar and echo everything tastrekker says.
Some describe that walk as a "bit boring", but that's subjective.
There's also many opportunities for other sidetracks to mountains, features along the way.
Whet your appetite for a return trip.
Your 2 days exploring and 2 days walk out could see this accomplished easily, or 1 day in immediate Walls and a rambling 3 days out taking in side trips.
Mersey Crag, Turrana Bluff, Fisher Bluff, Mt Ironstone.
Certainly grab copy of map or jump onto LIST and TasMap and look at it online, print out sections, laminate and make your own.
Default background is Topographic but you can change to suit.
Not sure if I'm "teaching a grandmother to suck eggs" so aplogise if such re map.