I don't know what the FTW is, but I like two panel file managers; unfortunately something like gnome-commander hangs on large searches and sometimes crashes: if it worked 100% well it would be great.
For other choices I like LMDE with an xfce (old standard Linux menu, not a Suse slab type), and a minimally cluttered desktop with only a few icons, no fancy theme, screen save or wallpaper, and no animation or even activity/busy application launches, if it doesn't in the time I expect, I give up and start it again; as using an application informs me as to its normal startup(load) time..https://wiki.ubuntu.com/Slab
If i really had to be that productive, fast application switching, I would probably use one of the multi-screen (window )applications to jump around open apps
--of course I would then need lots of RAM and a goodly amount of hard drive storagehttp://www.gnu.org/software/screen/
--possibly something like that, not GUI (a terminal shell), it would have to manage the GUI applications launches, but it wouldn't be weighing down the system with a GUI-based multi-windows management controller: with plenty of RAM, I wouldn't care and would lil;ey just use the windows switcher and probably add more than the default of 4 windows..
I remember that Beos offered 32 windows (sessions), but it is not ready for prime time and since being orphaned, hasn't had much in the way of driver support (Haiku..)