The good news is that you already did well the first time.
The bad news, I think, is that you aren't going to be able to ignore the quant section in your studies. Raising the math score to a 48 or 49 will take a LOT of pressure off of you in terms of hitting 720.
For me, the biggest jump in verbal came when I read a post about solving the SC questions in less than a minute. I think this is important for most people, because a little extra time reading the passages and the CR questions can make a huge difference. I noticed that, by giving myself a little extra time for these question types (CR and RC), I got almost all of them correct. On the other hand, my hit rate at SC did not change much after spending less time per question (with practice of course). I guess, for me, I always ended up guessing to some degree on the SC questions anyway, especially the ones I saw after getting all of the RC and CR correct.
Specifically, in terms of skills, I think the best thing for Verbal is to practice at a faster rate than you need to. For example, every morning before work, I would take one or two of the most difficult RC passages I could find, as well as ten or so SC problems. I would think: Ok, for these RC passages and their problems, I should spend no more than X minutes each. Then, I would give myself 10 minutes for the 10 SC problems, and do the SC problems FIRST. This way you simulate the real test. If you don't solve those SC questions in 10 or so minutes, you will NEVER be able to answer the RC questions correctly. Push it to the limits, and when you get used to it, it will help with the verbal confidence.
Doing this over and over again really paid off for me. I ended up scoring a 720 even with a Quant section that I considered to be a disaster, and a slightly lower verbal score than I expected.
PS I know it's hard to find good RC passages. Don't hesitate to look outside of business school books. For example, I used my roomate's Kaplan Verbal
MCAT book. Practicing those passages at GMAT speeds is the kind of training that pays off.