Not sure if it's ideal for you, but you could probably use QGIS cloud, set your paths to display by type and have images displayed via point/exif location data on mouseover. You'll probably have to edit the tables of the files you're using (.gpx, .kml, .shp etc.) a little but it should be pretty straightforward. If you don't mind writing any code most of the workflow could be automated once you get a good idea of how you want everything to run.