Hi aidyn,
First off, a 690/Q49 is a fantastic score, so it might very well enough to get you into your first-choice School. As such, a retest is probably not necessary. Since you've been discussing how you want to put more time into building up your profile, you would likely find it beneficial to speak with an Admissions Expert about your overall profile and plans (to make sure that you are putting together the strongest OVERALL application that you can). There's a Forum full of those Experts here:
https://gmatclub.com/forum/ask-admissio ... tants-124/GMAC has publicly stated that the Official Score that you earn on Test Day is within +/- 30 points of actual ability. Assuming a similar 'swing' in how your CATs function, your various CAT score results - along with this Official Score - show that you essentially performed the same each time (690 +/- a few points). You handle certain aspects of the GMAT consistently well, but you also make certain consistent mistakes.
I want to reiterate that I do not think that you need to retest, but if you decide that that's something you want to do, then you might also choose to purchase the Enhanced Score Report. While the ESR doesn’t provide a lot of information, there are usually a few data points that we can use to define what went wrong on Test Day (and what you should work on to score higher). If you purchase the ESR, then I'll be happy to analyze it for you.
GMAT assassins aren't born, they're made,
Rich