Your goby isn't going to be very active. That's just the way that watchman gobies are. If you want his behavior to be more interesting, you can try adding a pistol shrimp (alpheus spp.) and see if they will pair up, since he is a shrimp goby. If you can get them to pair, the symbiotic relationship is fascinating.
Your banggais are acting normally IMO. They tend to just hang out. The royal gramma on your list isn't a very active fish either, but any dwarf angel certainly will be.

Just resist the urge to stock quickly and be sure to take it slow, and your tank will be great.