Oh dear, I tried not to respond but i couldn't help myself. Stop me if I go off into the woods.
My guess, Chris, based on your fleeting reference to GF files, is that your SMT machines are Siemens Siplace. If this is so then package orientation definitions are limited by the fact that the long axis of the nozzles that are used to pick the parts are oriented along the x-axis of the package. To use the trusty SOT23 example this means that the single lead is usually defined pointing upwards when viewed in the Package Form editor - this defines the 0 degree orientation of the part. (The package could also be defined with the single lead down but that just complicates things - but it cannot be defined with single lead to left or right because that would cause pickup problems on the machine.) Continuing on, if the SOT23 is presented to the machine in tape where the single lead points left then that feeder must have a 90 degree pickup angle - if it points right then it must have a 270 degree pickup angle. This business with the nozzles tends to complicate the definitions of SOICs compared to TSSOP type packages. SOICs are typically defined with leads along top and bottom and pin one bottom left. But with TSSOPs the body "width" tends to be longer than the "length" leading the package being defined with the leads down left and right sides and pin on top left (or bottom right). This is confusing because SOIC and TSSOPS are essentially variations of the same thing.
I sense a lot of blank looks now so I'll stop and get back to my real job.
So, having said all that your current method, in the absence of a universal CAD translator or pixie dust, seems like a reasonable approach... you seem to understand your problem and are dealing with it in a sensible way. I'm sure there will be someone out there willing to sell you CimBridge, CamCAD, TIMMS etc.
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