RA and reflect used to be good with inscription and give 0/5/5/5/5. I'm not sure but don't think that's still the case. Reflect also gives a pool to bounce spells back at attacker.
Protection is very useful but best used when toggled in and out of it on a caster.
I'm not sure that arch protect works at all, but if it does in theory if you were partied with someone you wanted to die for some reason you could handicap them with it's penalties... but essentially it's useless unless they've changed it.