#2 To slightly freshen up the women's division
In 2018 and the early stages of 2019, SmackDown's ladies' division was dominated by Becky Lynch, Charlotte Flair, and Asuka. The three women battled each other for the right to carry the title and the rest of the women were left to take part in secondary storylines and matches.
Rose had one shot at a singles title earlier this year but wasn't expected to capture it so close to WrestleMania. There was no way the Empress of Tomorrow was dropping the belt to her right before the Show of Shows. Instead, she dropped her title to Flair two weeks before 'Mania. At WrestleMania, the Blue brand's triangle of power continued as Lynch won both titles.
Following the Show of Shows, Bayley and Flair have been the focal point of the division. Bayley has had different challengers here and there, but for the most part, Rose and Deville have played the same role since debuting two years ago - secondary competitors.
By splitting the team up, it would provide a different look for the women's division on Friday nights. We assume Rose would be the heel, but maybe Deville is the one who turns on Rose and embraces her darker and more sinister tendencies.
The rosters definitely need to be slightly refreshed because the same four or five women have consistently dominated both shows in 2019 - Flair, Lynch, Bayley, Banks, and Lacey Evans. Alexa Bliss, Nikki Cross, and the Kabuki Warriors have had varying pushes throughout the year, but not on the same level as the other women. Some new challengers need to emerge and perhaps breaking up Fire and Desire will provide one or both women the chance to do so.