That's good to hear the 7th & Rio Grande Tower will start. That should help to burst the bubble for highrise development in that area of downtown.
And that's cool about StreetLights at Barton Springs (formerly Aquaterra), although, I'm still not sure about the design. It's supposed to be a long building, running east/west along the south side of that super block. I just hope it doesn't look too imposing and monstrous since it will be very visible as you approach downtown from the south. The only height I've ever seen for the building is 19 floors and 199 feet. That would make it the tallest building south of the river. The next tallest is the Hyatt which is 185 feet tall. Judging from the height of 199 feet with 19 floors, I'm assuming they're planning about 6 levels of above ground parking. Park levels usually are very low, maybe only 7 feet. So 6 of them would be 42 feet. That would leave about 157 feet for actual residential levels.
Here's the architect's website. They're also working on some designs for East Avenue. One of them is a 17-story apartment tower. They also have a 16-story condo tower planned that will overlook Lake Travis.
http://www.rhodepartners.com/webbrochure.pdf