GMAT Strategy

Hi,

My GMAT date is 11th June. So I have 3 weeks for the test. My target is 750+. Till now I have completed OG: 10th once and revised SC part once to make sure I know reason for every correct and wrong choices of all questions. 13th OG once.

My Mocks score read like this..

GMAT Prep 1: 730( 3 months back)(quant 51, verbal 38(don't remember exactly))
GMAT prep 2: 630 (2 months back) - timing was pretty bad... spent some 10 mins on 1 question in quant and managed to repeat the same folly in verbal...

MGMAT 1: 710 (Q: 47, V:40)this was 1 week back - This test showed me how I can lose it in Quant.
MGMAT 2: 730 (Q: 50 ,V:39) - improved quant a bit. But still have timing problem in quant..

I took both MGMAT tests under strictly Real GMAT conditions..

Over all my question is What I need to do in these 3 weeks? in short what are "Must dos"

My Problems:
1)Quant I found IR very tough.. I'm able to solve only 8-9 questions in 30 mins.Generally get 6-7 right. What should I do to optimize this score?

2)My target is 51 in Quant. I believe Quant is my stength. Still I'm messing up with timing and finding my self in a situation where I'm making avoidable mistakes on easy problems by coming under time pressure. How to practice to avoid this? I need to bring down my mistakes from current 10 level to 5-4 level. Also Any opinion whether original GMAT quant will be as tough as MGAT?

2)SC: I'm able to identify mistakes and generally know the reason for all the SC problems but on tough problems I am not able to decide between last two choices. I'm getting 5 wrong eachtime. What can be my problem.

3) CR: Clue less why I'm getting 6 wrong each time. I always get to a choice between last 2 situation and invariably chose the wrong choice. Dont' understand what to do to fix this. My plan on CR is

for strengthen or weaken problems-- remind myself of conclusion while reading the choices.
for conclusion probelms - mechanically think in almost mathematical manner.
for assumptions questions - apply if this is not true will the conclusion fall apart test.
for others just apply logic

What can be my problme. Why I may be getting it wrong after narrowing down to two.

4) RC: I am getting last RC wrong. I'm not taking notes as I believe it makes me waste time. First 3 RCs i may get 1 question wrong .. What to do to get tough RCs right.. or what should be my strategy with the RCs

Please suggest what I need to do in these last 3 weeks.