I think I understand what you mean. There is no prize money, so I better rewrite my previous sentence:
Let's make a contest-like game. Create a simple code like this and try to beat the high score of currently 4.7 seconds for 1million bech32 addresses without using GPU.
Prize is incentive not purpose. A purpose could be something like a tool that would generate vanity addresses so you'd need the fastest possible algorithm and implementation that is capable of checking very large number of addresses per second. Or the purpose could be a recovery tool where you have 8-9 words out of a 12 word seed phrase so you need to check millions of addresses that is generated from it to find the right combination.
The importance of "purpose" is that it will also clarify HOW to implement it. Right now if I understood the code correctly, you are just aimlessly writing the addresses to disk so there is not much to work with. But if the example I used is the purpose (ie vanity address), there is no need for IO and its bottleneck hence the algorithm changes, there is also no need for Base58 or Bech32 encoding, there is also no need for ECMult each permutation. These very simple changes lead to significant increase in speed.