The Kalam Cosmological Argument

[Sheldon]

What is moral perfection? 

Subjective obviously, it even has apologists like Lane Craig claiming genocide is moral perfection.

 Omnipotence is reduced to "able to do anything 'possible'", which is an unspoken limitation on what is doable -- which limitation Christians won't admit for their god.

The limitations bump up against our definitions of "omnipotence" and "omniscience". That prefix, "omni-", has a specific meaning, and that meaning is that the suffix is unlimited.

Agreed, the word inevitably leads to contradictions, and post ad hoc rationalisations from apologists.

That's not even to address whether an omnipotent god can act in a way that he might surprise himself. If he can surprise himself by a whimsical decision, he isn't omniscient; 

Well the notion has larger problems than that, several posters myself included have mentioned the problems omniscience presents for any notion of free will or autonomy of choice for humans. However this must logically apply to the deity as well, if it is omniscient it must know what it will do, before it does it, thus it cannot have any autonomy itself. 
Parenthetically, since any notion of morality must involve autonomous choice, it also contradicts the idea that we or the deity could be moral at all, let alone that it could be perfectly moral, and of course if it has no autonomy of choice, that is the very antithesis of omnipotent. I have seen the kind of mental gymnastics and special pleading required to square this circle, in any number of debates.