I assume we'll have the ability to choose between 2, 3 and single class configuration in the FMS like we can for the 737? I would appreciate this feature. thanks!

2-4 would be most common for the 777 :-)

I kinda prefer a load manager that can work within FSX vs flipping through various FMS pages or perhaps have a special EICAS screen for such tasks.

EICAS/EFB screen would be an elegant solution, but I still like the MCDU interface better than separate load managers, in-sim or separate.