Kgun, I liked your post very much!
Google displays the suggested phrases from its users searching terms database.
It's means users create those terms, not Google and its "magnificent imagination".
Currently, I believe
SEO experts should focus the users searching preferences and not that feature.
By now, we can't predict if most of the users will prefer to use that suggested phrases. I'm for example prefer to see that feature as a simple "auto-complete" box. Lets admit, The suggested box is pretty stupid. It is suggests only the sequel of the phrase: no synonyms, no smart suggestions, related terms.
The tail of suggestion box feature is very short and thus not always efficient.
Now
SEO thinkers may ask them self some new questions about the terms they would like to promote, but I think terms such as conversion rate, accuracy, website purpose will remain the major considerations for
SEO.
Bottom line, I still don't predict any search revolution.