1) If the stud spacing varies so much, you may want to consider blowing in cellulose insulation instead of cutting and fitting FG batts. It packs phenomenally well and gives better air sealing and better noise abatement than FG...even blown in FG. should moisture ever get inside the wall cavities, for whatever reason, cellulose handles the moisture better than FG.
2) With the walls open, and the stud bays running from "basement to attic," it's a great opportunity to install fire blocking. I'm in New England, and up here it's required so no stud cavity is greater than 10' long. It prevents long stud bays, as your balloon-framed house has, from acting as chimneys, essentially providing a free path for a fire in the basement to quickly travel into the attic. Cheap and effective insurance. I guarantee that if you suffer a fire down the road, when the inspector/apppraiser from your insurance company does his thing, if he discovers that work was done and blocking was not installed, you may very well be out of a settlement.
It may save your life, the lives of your loved ones, and a hellacious lawsuit should you sell a "defective" house and the buyers suffer misfortune after the sale.
3) Vapor barriers. Construction in a cooling envoronment (TX) vs a heating envoronment (CT) is somewhat different. Up here, it is not wise to have two vapor barriers in a wall. I honestly don;t know about Texas. By having a plastic barier on the interior and a RFBI barrier on the exterior, you could be setting yourself up for moisture-related rot problems down the road. Again, your locale may certainly be different than mine.