Had an annoying thought.
I cast a framework miracle whose purpose is to be a permanent feature of the deity. In effect, it provides a secondary effect. The difference between transforming oneself into a porpoise and a miracle that allows me to change shape at will.
I think this should be an Advantage, something that increases the multiple rather than decreasing it.
My other thought is that maybe this sort of thing should only be allowed through artifacts. That way, there's always a risk that the artifact will end up stolen, destroyed, or otherwise not in the control of the sponsoring deity.
OR prevent such miracles from being placed under the Nimbus. When Protean's shape changing mirace becomes that of his opponent, who transforms him into a stink beetle? Gives new meaning to 'private hell'. (Of course, nothing prevents him from ending his manifestation of avatar and all the miracles upon it.)
I think it may be best to consider permanently placed miracles in layers, like Nimbus currently is.
Again, I have nightmares of balance issues. I don't like the idea of combat miracles without extra cost, although by the rules, it's possible to create a 'Permanent' miracle and then define it as being able to be retargeted/suppressed and re-activated.
Also, if I'm correct about this being legal, it really ought to be the sort of thing that's spelled out obviously (like Nimbus), and should be balanced against these permanent defences. For example, if a permanent attack fails against a Nimbus, that particular miracle should never be able to pierce that Nimbus. OTOH, each 'payment' of a miracle is considered a seperate attack. As made clear in the divine combat example, no deity is going to just stand there while their defenses are crumbling.
Sorry, babbling and crosstalk from the Inheritance issue. I think I'm on the verge of answering my own question(s), but it's going to be an answer that may depend on how artifacts are handled. And it's not coming tonight, sorry.