Whew, this is a lot of information. A quick piece of advice to you and to anyone else who might be reading this: try to really distill down to get at the exact questions you want answered. There are about a dozen questions strung through this post and I apologize that I won't be able to answer all of them.
What I can tell you is the following:
You should not limit yourself to one-year programs if you don't have a major reason for it, as it simply slices the field too narrowly. Especially because...
You are going to have a very difficult time with that GMAT score. I know you don't want to take it again, but you can probably rule out most top 20 schools, both in the US and abroad, because they just aren't going to carefully review your file in many cases. It's so far below the average of most elite programs, that you get sort of informally screened out a lot of the time. If it was 20 points higher, I think you would be in safer territory to at least get fair reviews, but right now you are in a dangerous place.
Another factor that is going to work against you a bit with US schools is your work experience being above the average. It brings up the question of "why have you waited this long to make your move?" This is less relevant with EU programs and those in India, where more work experience and older ages are bit more of the norm, but 7+ years WE and sub-700, coming from India, is one of the toughest hills to climb at most American schools.
In short, I would expand your program interest beyond one-year programs, I would look to EU and Asian programs (ISB, HKUST, IESE, Oxford, etc.), and if you think you can get a 680, I would seriously consider taking the GMAT one more time.
Hope this helps.