I have heard that Krusader has a great "commander" feature that allows you to start a file transfer and queue additional files to be transferred. They are transferred one by one in order, rather than kinda randomly all at once.
Is it possible to do this in Nautilus (or with an existing Nautilus extension), or is Nautilus not intended for this kind of thing?
Is it currently possible? No. Would it be awesome? Yes.
I don't think it's a case of not being intended, it's just something that hasn't been done. If memory serves correctly, it took KDE a while to get it done.
And it's all fairly low-level stuff. It's not a simple bash script that's running cps and mvs in the background so I don't think it's going to be as easy to hack into as you might like.
You might want to find a GIO developer (assuming it's still GIO that handles these things) and shake them until you know why this isn't in there yet. Unfortunately, GIO developers are a stealthy and paranoid bunch. They know you're looking for them so you might have to file a bug against it on the Gnome bug tracker to lure one out.
But in seriousness, remember the devs don't work for you (unless, bizarrely they do work for you -- which would be a strange coincidence). If you do find one, try not to startle them by running up to them, shouting and waving your arms around. Just quietly ask if it's a planned feature and if there's anything you can do to help.
It is not possible in Nautilus, but it may not need to be. (Although see Oli's answer on requesting such a feature.)
The KDE equivalent of Nautilus is Dolphin, also a file manager with navigational and spatial features. Neither aims to be an orthodox ("two-pane") file manager, which Krusader is, so comparing Nautilus and Krusader features doesn't (necessarily) make sense.
Instead, you may want to simply use Krusader, or a Gnome-based orthodox file manager, namely Gnome Commander.
