a week of studying ? no wonder you got the same score.
If you're looking for a 700+ score, then think about at least a month of dedicated studying.
GMAT is NOT easy, yet NOT Impossible.
I think all different types of verbal questions are weighted equally the same, or at least very close.
I believe the first 10-15 questions are "relatively" more important than the rest of the test, but Not much much more important. to get a good score you have to consistently answer questions correctly throughout the test.