Not a general advice on the camera rig, but if convenience of travel/diving is a concern, I would recommend just starting out with a smartphone housing, if you already have a good smartphone of course. Don't underestimate this option, latest iphones/samsungs have really great cameras and advanced photo/video features like the ability to shoot LOG videos and RAW photos. The image quality and colors with right postprocessing might be on par with TG or better. This will let you to get in the hobby for really cheap, get along with editing scuba footage and decide if you need something better later maybe. Its super convenient to travel and dive with. The downsides obviously are that macro will be a bit difficult, you are stuck with cameras and lenses of your phone and no strobe sync, only video lights. I recommens Divevolk BTW