Regarding question 2, I see that I didn't word it properly. I'll try again:
2. Is there such a thing as an ideal gas of identical but distinguishable quantum particles?
As a specific example, suppose we are talking about one million atoms of helium-4 and all atoms have their electrons filling the 1s orbital. Thus all atoms are identical. But put these atoms in a cubical box (that is otherwise empty) measuring 100 meters on a side. It seems like each atom will have on average a cubic meter to itself, so I can distinguish atoms (at least for some time) by saying there's one in that cubic meter, one in that cubic meter, etc.
To put question 2 another way, does anything special happen when D >>> L > R where L is the thermal de Broglie length, R is the size of a gas particle, and D is the average distance between gas particles? I put >>> to mean hugely bigger, not just the ordinary bigness of STP. Special might mean the Sackur-Tetrode equation changes, for example.