i think they're going to feature her more in merchandising and promotional stuff, at the very least. i've mentioned it in another thread but apparently the ashley club nintendo reward and band brothers dlc sold well.
The weird thing is that I would say none of the individual appearances would normally mean that much when seen individually. I mean:
1: rhythm heaven: everyone else from ww is in too (although ashley is the first to appear in rhythmware, and the only character to appear outside it)
2: band brothers p: ashley's song was also in the previous gaems (although this time, it's paid and is one of the most expensive piece of dlc for the game)
3: mario maker: has really out-there choices for its costume selection (I mean, we're not expecting an AAA reboot of Big Brain Academy, are we? lol)
but having these appareances so close to each-other combined with the Club Nintendo thing... eh, I don't know, but it does give some hope.
(i really doubt they're going to jump straight to an ashley spinoff gaem, though : p)