Hi Michael, I agree with Tom and Todd. It is mostly about access. I usually find it simpler to rail first, working from inner structures and moving outward finishing with deck edges. I typically rig last.
As for complex decks, I bend the photoetch if possible, but it is usually necessary to cut it into small sections to get an exact fit. I did this on the Olympia superstructure:

Although fiddly,installing the railing in short runs enables me to get very precise fits from generic rails, and it also offers the advantage of easier replacement of sections in the event of damage.
Nice job on your own railing job so far, by the way!  
