a spell to siphon excess energy off the shield into a ring or other object would probably make the shield charms more complex and probably need more energy.
Ive wondered about a 2 stage shield charm.
1st stage only for bullets and weaker physical objects and takes very little energy.
2nd stage protects from absolutely everything and takes huge energy.
about the rings, they were insanely useful i doubt Jim will do it but honestly Dresden should sew 30 of the triple rings onto his duster somewhere. no reason to have just the staff spell
harry can take out only so many guys in a given time period with his own magic before he passes out, stuff like the rings that lets him take out extra guys is always great. on that note he needs some guns, Dresden could handle the recoil on and conceal some huge guns. id say conceal one powerful revolver for beasts and something like a glock 19 for people maybe some grenades and larger guns for battles
Ive always hated how much of a glass cannon Dresden is, if he goes about openly it would be very easy for him to die in a surprise attack from a few guys with scoped rifles.
to make him tougher id say he needs enchanted boots and shin protection, enchanted vest, hardened vampbraces (he always blocks blows with his forearms).some type of head protection for battles at least