Hi notmygmat,
It sounds like you've already identified some of the problems with how you studied the first time. The big issue is ultimately "consistency." The GMAT is a specific event that you CAN train for, but it does NOT seem like you trained in a realistic fashion for the full GMAT.
To hit your goal score (650+), you're going to have to start much of this process "over." While you've clearly picked up some Quant skills, you're likely going to have to do some work in this area as well (meaning that you can't just focus on the Verbal section and fix all of these problems).
I have a few questions about the work you've done so far and your timeline/plans:
1) When you took your CATs, did you take the ENTIRE CAT (including the Essay and IR sections)?
2) On Test Day, did you have trouble finishing any of the sections on time? Did you have to rush through a bunch of questions at the end just to finish? Did you leave any questions unanswered?
3) When are you planning to apply to Business School?
To help you set your expectations going forward, you should plan to spend 3 months of consistent study time on this process. During that time, 10-15 hours per week (or more) will likely be the norm. You're also likely going to need to invest in some new GMAT materials.
Thankfully, the GMAT is a predictable, standardized Exam, so you can CAN train to score at a higher level.
GMAT assassins aren't born, they're made,
Rich