1. Is something good because God says it is good? or
2. Does God say something is good because it is good.
This is a rather simplistic representation - the idea is to distinguish between God being the source of morality or endorsing some independent or 'external' morality.
... we believe that God's nature itself is the standard of goodness.
This appears to be a restatement of horn 1 of the ED, as it has the same problems - for example, if we assume that God's actions reflect God's nature (what else does 'nature' mean in this context?), then we can propose a syllogism:
P1 Actions consistent with God's nature are good (moral), while actions inconsistent with God's nature are bad (immoral).
P2. God's actions are always consistent with God's nature.
P3. From 1 & 2, God's actions are always good (moral).
P4. God's actions are best evidenced in scripture (the Bible).
C. From P3 & P4, it is good (moral) to perform the actions attributed to God in the Bible.
It seems to me that many of the actions performed by God in the Bible would not generally be approved as good or moral if performed by us, which suggests that what is moral for God is not necessarily moral for man - in which case God is not the moral standard of goodness for man.
The circularity of the claim is troubling: God's nature is the standard of goodness - why? because good is morally better than evil; and good is morally better than evil not because of some external, independent morality (horn 2 of ED), but because goodness is the character of God's nature...
If the standard you use to assess God's moral goodness is God, it's a meaningless assessment. To say 'God is good' only means 'God is himself' and 'God reveals what is good' only means 'God reveals whatever he reveals'. You can apply this to anyone or anything: e.g. Trump is morally good; what does it mean to be morally good? it means to have the moral character of Trump; but why does it mean this? because Trump is morally good...
So being morally good means God has the moral character of Himself, whatever that may be. This doesn't imply anything about God or his concern for our wellbeing, it just means God is Himself. His commands & actions could cause untold harm and suffering (as in the Bible) and still be good by definition. He could have hatred & contempt for all beings and still be 'good' by definition.
It seems to me that 'goodness' in the context 'God is the standard of goodness', is meaningless or redundant; God is the standard of Himself, whatever that is - effectively a meaningless tautology.
E.T.A. Incidentally, I think that raping little girls for fun is wrong, no matter what anyone else thinks; but that's just my personal opinion.