I think it'd be best to approach this as 7k+1.
I would then recreate another map to be a 7K map that's basically auto-scratch in BMS
But this removes the fun from the scratch sounds from songs that have a lot of scratches, which would be the reason for people to want a 7k conversion.
I vote for
1) 7K+1 direct conversions w/ a 7K possibility (which would just remove the scratch column)
2)I would love to have Normal/Hyper, since I myself can't play a majority of Another maps.
3) it would be cool if peppy added a mirror mode in mania. So the P2 Players can play with right shift lol.
And i vouch for those keysounds. It's what makes BMS so gud