As for printing vertically, when I was printing hand covers, I had them oriented vertically on the table so it buildings from the table up to the finish height. I printed an insert for the forearm flat on the table, so it was printing horizontally in circles to build up the layers. The difference in the appearance, even though both were printed at .3, was huge. The horizontal orientation you could clearly see the layers, whereas the vertical blended in a bit more.
I was thinking about crushing all of it as best I can, melting it down into slugs that can be run through a high-temp glue gun to make assembly less awkward. The temp on any standard 'high temp' glue gun is still a bit on the low end, but it will get the PLA to a point where it can be pushed through. Melting the pieces together has been the best method I could come up with for assembly, glues take too long and I've had mixed experiences with super glue type quick sets. Plus with the heat introduced to the parts it makes matching the pieces up a little bit easier with the warping you were talking about earlier. It does, however, make for extra sanding and filling if too much heat collapses the internal supports.
With the inevitability of using bondo or any other filler, do you think cranking the resolution up to a .4 would speed things up and give more grip to the bondo on parts that don't have any minor details to be preserved?