I don't understand the Silver Ring.
On the other hand, I count people who think that they can't use Katakotl's Ring as either dedicated warrior-only types, or not having an imagination when it comes to playing a caster on regular shards (Siege, OTOH, I understand why you'd not invest the work in getting it).
It's what makes many triple caster templates viable. In my case, my mystic/mage/weaver uses one set to Mysticism. That way, I have 120 Mysticism, 120 Magery, 120 Eval, 120 Weaving, 120 Focus, and (depending on what I'm doing with the character at the time) either 120 Fishing or 100 Inscription (remainder in Med). The synergies between the casting skills' spells can be incredible. I've seen others I know running similar casting templates (no fishing), with necro instead of one of the other casting skills (or even instead of Inscription, going for quad caster). After all, you really only need 120 real in the skill that you have you use your mastery from. And, while I might lack a bit in luck (I've never believed it enough to make luck suits for non-tamers), my human caster has 62/70/70/70/70 resists, 112 SDI with book, and max or higher in all the other caster suit properties with a 0-resist necklace.