Your SPG is simply a back up to your brain. You should not have to check it much, so it being out of the way on your hip simply makes sense. If you start clipping it to a chest dring, then when you add your backup light, and possible stage and deco bottles, you end up with a mess of clips there. Then people start adding more drings and throwing equipment at it to fix issues that should not be issues in the first place. With your SPG clipped to your waist, you should be able to just look down at it to check it anyway without unclipping.
What type of 7' hose do you have? Is it rubber, braided, or MiFlex? Some types have more "memory" to them and like to stay coiled. That is why I stay away from long MiFlex hoses.
AJ and Ian already touched on the other issues, so I really don't have much else to add. Good luck, and I hope you enjoy your new purchase.