With your draw length, IMO you are only handicapping yourself by going with a longer brace height bow (unless your form is iffy).

Regardless, I prefer a longer bow with a decent brace (i.e. 6.75" to 7.25") rather than a short bow with a big brace. Longer, heavier bows are more stable during the entire shot sequence, and I find that added stability helps to keep me from making the mistakes in the first place that a higher brace would help with.

Did that make sense?

EDIT: I always recommend shooting the bow near it's peak weight. Speed diff will be small on some modles, but the bow will have the proper limb preload, brace height, a better feel to the force draw curve and will generally be quieter with less vibration