I think there is a subtle difference. The word 'so' means manner or degree. This overlaps with the meaning of 'so much', but the two are not equivalent. The phrase 'so much' implies a degree, amount, or extent, but it never suggests manner.
Consider the verse from the Bible, "For God so loved the world that he gave his only Son..." This verse could imply quantity of love (extent) or it could imply manner of love (charity). The word 'so' invites more interpretations than the phrase 'so much'.
Another example. "Why did you say so?" versus "Why did you say so much?" The two are clearly not equivalent. They mean very different things. Thus, I would caution you against thinking the phrase 'so much' to be interchangeable with the adverb 'so'. There is some overlap, but many differences.
In this respect, I do not think your two sentences are equivalent. I also think your first sentence is much more idiomatic than your second. I would go with that one.