GMAT Retake? When your score is above target schools avg?

I just finished my GMAT retake and was happy/relieved/overjoyed to see a 670 (Q44, V38) on the screen at the end. This marked a 50 point improvement from my effort nearly two months prior.

Now, a question for you gurus.

My target schools predominantly have avg accepted GMAT scores of 610-620. These are mostly tier-2 Canadian Bschools. Although my GPA, WE, etc aren't laughably weak they are WELL short of being overwhelming to an adcom.

My goal was 700+ not only out of personal challenge, but also because I figured if I scored that high relative to the avg scores of my target schools that they would be willing to overlook some of my weaker areas. In essence, they may be sort of 'wowed' with my GMAT score and willing to let it overshadow other, weaker, elements of my application. Now, I will absolutely put in 100% effort on my essays & recs and will be applying early to all my schools....BUT... do you guys think it'll be worth a retake at this point or will a 670 be sufficient to achieve the slack I need to cover my weaker areas of the app?

I'm also concerned about rewriting in case I score lower somehow and spook adcoms with a downtrend and that, while they may say they are only intertested in the highest score, this scenario may negate my previous (higher) score.

Any thoughts here fellas?