Hi paul77,
I do think studying for quant makes the most sense, and here is some advice on how to move forward with your quant prep.
I recommend adopting a prep strategy consisting of topical learning and practice. In other words, focus on just one topic at a time and practice that topic until you achieve mastery.
For instance, let's consider your study of Number Properties. First, immerse yourself in all aspects of this topic, and then focus solely on Number Property questions. After each problem set, take the time to delve into your incorrect answers. This self-reflection is a powerful tool that allows you to understand your learning process and make significant improvements. For instance, if you made a mistake in a remainder question, ask yourself why. Was it a careless error? Did you not apply the remainder formula correctly? Was there a concept in the question that you didn't grasp?
By meticulously analyzing your mistakes, you will efficiently address your weaknesses and, consequently, enhance your GMAT quant skills. This process has been unequivocally proven to be effective. Number Properties is just one example; follow this process for all Quant topics.
Here is a great article you can check out for some more advice:
Improving Your Accuracy on the GMAT