Tell your dad that probably 2iu a day taken over long spans of time would make a decent difference in the way he feels. More than that is nice, but a pain in the varied spots
And unlike what some longevity clinics might suggest, the 2iu first thing in the morning upon waking is best, theres good clinical grade research for that. If your dad doesn't already have a doctor in mind, let me know I can help you find one.
Healing is a rough one, particularly if you want to remain as legal and all prescription. there are a few of the peptides currently in research that have similar properties, or there is a the ability to directly inject IGF variants. Part of raising GH for healing is to cause the creation of more IGF, which aids in muscle tear healing. The L-Dopa products like Applied Nutriceutical's IGF-2 or any of a handful of others (Powerfull, Somnidren-GH, etc) all help increase the natural production of GH, which will help somewhat.
Really for the most part, getting leaner is at least 90% diet (including what you burn in cardio), and less than 10% anything else. Do you know what your estrogen levels are like? that is something that can make it harder to loose fat, its a battle i've fought for a long time