Hi u1983,
While you don't necessarily need to define your Overall Score Goal - as well as the Schools that you plan to apply to - having specific Goals in those areas can help you to better focus your studies (and essentially define the point at which you would be 'done' with your GMAT studies). For example, if you plan to apply to a School/Program that places a greater emphasis on the Quant Scaled Score, then you might end up needing to improve in certain Quant areas (and adjusting your studies accordingly, instead of 'hoping' that you Score higher in that section).
While many Test Takers are concerned with how "fast" they work through Verbal prompts, the goal there is NOT to be "fast" - it's to be "efficient." On the GMAT, efficiency involves a number of different areas, including your content knowledge, 'active' reading, taking proper notes (doing work "in your head" is NEVER the best way to approach a prompt) and using the proper Tactics (since most questions can be approached in more than one way, it might be that "your way" is the "long way" - and a more Tactical approach would help you to be more efficient).
Raising a V29 to a V40+ will require that you make significant improvements to how you handle all 3 major Verbal questions types (RC, SC and CR). That training will likely take at least another 1-2 months of consistent, guided study - and as such, you might want to consider pushing back your Test Date. Thankfully, the GMAT is a consistent, predictable Exam, so you CAN train to score at a higher level.
GMAT assassins aren't born, they're made,
Rich