Should I retake a 700 (Q42, V44, IR8)?

It will depend where you're applying, but for more Quant-driven programs, you'd usually want at least a Q45 score. Your Verbal score is outstanding, and while your overall score will be slightly below average at top schools, a 700+ is normally acceptable.

So if you have reason to believe you can get a higher Quant score in two weeks, I think it would make sense to try. Hopefully you've taken some of the official GMATPrep tests, and if so, you'll have some impression of your level in Quant. If you were normally scoring above Q42 on GMATPrep, then you'll very likely do so on a test in two weeks. If the Q42 was higher than most of your diagnostic scores, then you'd need to make some genuine improvement before retaking to be confident of a higher Q score.

It's certainly possible to make a lot of progress in two weeks, but you'd need to identify quickly what you need to do to improve. Without more information about your Quant performance, I'd just be guessing what you need to do - it might be that you're making some careless errors on easier questions, or that you have some gaps in your foundation, or that you're getting all the easy and medium questions right and just need to learn some methods for medium-hard questions.

I'm not an admissions consultant, so if you want to know about specific schools, and about how well your profile compares with those of other applicants, it would be best to direct that question to an admissions specialist. Good luck!