Redis is a series of tradeoffs between simplicity, performance, and power. For the moment, simplicity won as far as keys go -- they're all strings, period, end

Redis is a series of tradeoffs between simplicity, performance, and power. For the moment, simplicity won as far as keys go -- they're all strings, period, end of story. Supporting other key types is potentially useful, but brings complications, some of which will be visible to users of Redis. Your own measurements are telling. Your memory usage went down by about 82%, packing the integers brought that to a bit less than 86%. It's easy to justify a small increase in complexity to save 82%, it's a lot harder to justify even more complexity to bring that number to 86%.