I'm not sure what you mean with Venusian colonization. The surface is so utterly hostile that all probes we've managed to land only last for at most a few hours

I'm not sure what you mean with Venusian colonization. The surface is so utterly hostile that all probes we've managed to land only last for at most a few hours due to the intense atmospheric pressure, corrosive atmosphere, and temperatures hotter than the melting point of lead. Floating balloons were considered, but it turns out those have a whole host of practical engineering concerns that rule them out. Plus, getting back into orbit is nearly impossible from said cloudtop balloons. You'd basically need a full sized orbital rocket like the Falcon 9 because the gravity is basically the same and the atmosphere is still a major concern.