Dustin - I don't really have a dog in this hunt (as someone once said), but it seems to me the advantage of using an elevated hinge point and simply a butt joint on the track, roadbed, etc. is that its the most flexible in terms of making changes as you go along. The elevated hinge might be a bit harder to 'hide', but you'd have to find a way to hide the hinge in any event (if that is an important consideration...).
Another important consideration - independent of the hinge point - is to make sure you have a horizontal alignment method where the bridge meets the rest of the track when the bridge is down. I don't see it in the pictures you've posted (may have missed it). the lateral match is a pretty tight tolerance.
Looks like a fun project all around.
