Thank you for the Mew! And I'll take a look into your link a bit more; it looks interesting. Looking through it at a glance, it appears that while the RNG makes some Pokemon not possible with max IVs, due to a few variables (such as the equations for how specific impossible sets would be determined and that some Pokemon are available in multiple areas, making more unique equations to verify all 151 Pokemon), I don't think Nintendo will be checking this. Still, this is a fun find, and I'm glad you posted it!
Since this project was just a "spare time" deal that I coded every now and then during the past 5 or 6 days (with days missing) with the goal of coding it quickly, I chose for it to be dependent of PHBankGB since I was already using it, and editing the Bank file for that homebrew was much more time efficient than accessing the VC save with a CIA build and editing that.
As for your question regarding gen 2 games; I would think Nintendo will release gen 2 VC games eventually. In the case PHBankGB (or another derivative) was updated/created to read those, I think it'd be fun to allow pokeSlow to edit those as well, considering their data structures are the same (with a few interpretation differences, such as shininess through the IVs). If PHBankGB won't be updated, it may be worth looking into adding VC save reading for pokeSlow, although this update would definitely take some time, should it be done. Since PHBankGB is open source, it may almost be better to edit that to read gen 2 saves, since it would require less (rather than rewriting save reading/editing for pokeSlow with everything PHBankGB already has, and then some, PHBankGB would need less things added, such as a few new checks for VC Identification, as well as not passing gen 2 Pokemon to a gen 1 save, and offset changes to accommodate for the new saves).
Will it be done? No guarantee. Is it possible? Heck yeah!