I don't think FF needed to be her ROL. Madonna was 39 when she did that album, going on 40 and was losing mainstream appeal. Britney on the other hand was 29, going on 30, and gaining radio support in her home market and I think FF's commercial singles definitely aided that. I think now she's in a much better place to make a ROL-esque album because it's far more crucial this time around because era 8 is seriously make or break for Britney's career.