Using 'so' and 'much' / Synonmns for 'backwards'

Many kind thanks in advance to whoever can answer the following question. In regard to the words 'so' and 'much', I have had some EFL students I teach experience some difficulty in constructing sentences with the aforementioned words. For example, this is a sample sentence:

What else has been so much improved?

I want to be able to explain to them how 'so' and 'much' are best used. I know that 'much' is generally used for negative statements (e.g. I don't have much money), questions (e.g. Do you have much money?) and comparisons (e.g. I feel much better today than yesterday). As for 'so', I think it used to show degree of something (e.g. This is so cheap.).

Again, I would like to explain how to best use these two words because they are often misused by my students.

Finally, what are some synonyms for the word 'backwards', as in someone who isn't very cultured or hip (e.g. My friend is kind of a backwards guy.).

Thanks again.