The trouble with the snake naming convention is that it is self-limiting. To give room for future growth, you'd have to start by calling the Mamba something more like "garden snake".
The product line needs to be split into segments. Something like the lower-end (Sidewinder), mid-range (Mamba), and upper-end (Viper). And then add numbers/letters to the end of the name for specific model and/or generation.