I have a little trouble following those figures. It almost looks like you're "adding up the breakers."
I would approach a load calc a bit differently.
First, I would break up the area into different "occupancies," and apply the square foot calculation for my general lighting load.
I would add up all the general-purpose receptacles, and apply that watt multiplier.
Finally, I would look at specific equipment, and use the nameplate ratings.
I would review the plans, and the operations ... looking for continuous loads, additional lighting, etc.
This brings us back to the sq. ft. multiplier you started with; always calculate your known lighting load, and compare it to the per sq. ft. figure. The sq. ft multiplier is a minimum; you may very well exceed it. That sq. ft. multiplier is pretty much a useless figure, unless the actual loads are unknown (as in a commercial rental).
Let me give a general example. Assume a 20 amp circuit with 6 duplex receptacle. I would NOT base my calculations on 20A x 120V; rather, I would use 6 receptacles x 180 watts.
Or, if my shop lighting uses 10 fixtures, that were marked 1.1A on the ballasts, my calculation would be 10 x 1.1 x 1.25 for continuous use.
Likewise, the calculations are quite different for three phase than for single phase. It is important also to use the 'nominal' voltage of the system.
