Can't comment on the first part of the trip, but...
if you head up into the Wallace Creek drainage, the easiest way to exit is the Russell/Carillon Saddle, which drops you down to Upper Boy Scout Lake. You'd then have to backtrack up to Iceberg and the MR to do Whitney.
There is a crossing from Wales Lake to Arctic Lake that's supposed to be 3rd Class, but I've only heard about it (from a few different people), not done it.
You can head up fairly gentle scree slopes to Mt. Young and cross over to the bottom of the Arctic Lake drainage. That would give you access to the west, north, or if you cross Whitney/Russell, the MR routes on Whitney.