Hi Fabian123,
To start, studying for the GMAT now - far in advance of when you will actually "need" your Score - is a smart choice. That having been said, there are a couple of factors that imply that you may have gotten stuck at this particular 'Score level':
First, you have likely been studying too much over the last 7 weeks. I've never asked anyone to study 30+ hours a week - and while it's great that you might have had the available time to study that much, with that number of study hours, you would run the risk of 'burning out' before Test Day (and you have already increased the chances of that happening by taking so many CATs/mocks in such a short period of time). The 'swings' in your Quant and Verbal Scaled Scores show that your way of approaching the Exam leaves you open to making certain types of mistakes.
Second, from what you've described, your studies so far have been "book heavy"; unfortunately, many GMATers who study in that way end up getting 'stuck' at a particular score level. Even the best books are limited in what they can teach you; they also can't force you to approach questions in a certain way and their explanations are often one-sided.
If you are planning to continue studying in such high volume over the next 2 weeks and continue to use book-based resources, then there will likely be a limit to how much you can improve in that timeframe. In addition, if you have developed any 'bad habits' during your prior studies, then it will take time to define those issues and fix them (and replace those 'bad habits' with new 'good habits').
There's no harm in taking the GMAT in about 2 weeks, but if you're going to keep studying until you score 700+, then you will almost certainly need MORE time than that (without 'cramming'), so you can potentially save some time, money and stress by pushing back that planned Test Date. In addition, you would likely find it beneficial to invest in some new, non-book study materials for this next phase of your studies.
1) What is the minimum GMAT Score that you would be happy with?
2) Would there be a way to balance your University studies and your GMAT studies? In that scenario, would you be able to commit 15-20 hours to your GMAT studies without having to skip or miss your University classes/work?
GMAT assassins aren't born, they're made,
Rich