Unuseful or disregarded frames should not be stored in memory and disregarded. If i'm doing a handshake attack, it shouldn't eat 16GB of swap for 4 frames listed on-screen after 8 hours of constant attack.

You should order masks by efficiency (occurrences/key_space) because this will lead to the less guesses to crack passwords.

Looking at the top 5:
https://github.com/kaonashi-passwords/Kaonashi/blob/5239bd333ed34993b43126a4499606ba70086034/masks/kaonashi_masks_numbered.txt#L1-L5

And ordering just the 1000 in kaonashi_masks_numbered.txt by efficiency the top 5 are now:

673407:?u?u?u?u