Everything's looking good to me. I wouldn't agree that the jacket is too long, the sporran is in exactly the right place in relation to it. If anything you may be wearing your kilt too high on the waist which gives this effect - might look better with a waist coat. Also your sporran strap shouldn't really be through the belt loops (although I did wear mine in that fashion at one time because I don't have hips to hang it on). All in all you're looking good and doing the kilt proud.