I like the terraforming idea better, and we could get it started with todays technology, it would just be really expensive - simply build a bunch of solar shade cells and assemble them in L1 orbit between Venus and the Sun, and keep expanding the network until you cover Venus in night. Then let the planet cool for a couple hundred years - a lot of that thick sulphuric atmosphere might solidify and fall to the ground and get the atmosphere down to workable levels.