In fact, during the first Venera missions ( Venera 1 in 1961 to Venera 8 in 1972 ) the 'lander' was simply a bowl-shaped capsule and only 7 and 8 made it to the surface, although Venera 4 to 6 made succesful atmospheric measurements. The Russians were trying out several pressure-limits for their first veneras.
Landing into a liquid surface (there's no water on Venus) could have been an option I guess, as 1960s planetary scientists only had an idea of the Venusian surface by Radar measurements from Earth, although these may have excluded liquid surfaces?
The early bowl capsule weighing 400 kilograms could probably float but the later lander certainly lot as those had a weight of 700 kilograms.
Landing close together is linked to the fact that the Venera missions were 'flown' in pairs and arrived in the same weekly period at the cloudy slowly rotating greenhouse world
So the Venera pairs landed at similar longitudes as the planet rotates very slowly ( a day on Venus (244 Earthdays) is longer than a year on Venus (224 Earthdays) ).
In attchment a drawing used by scale modelers with approximate dimensions of the later Venera landers.