I've decided this topic has lasted long enough without new content.
Rosa Farrell- Her playstyle, I've decided, is like a bizarre mish mash of Ultimecia's fusileering Brave attacks, Firi's Straightarrow (and quite possibly his Shield bash mechanic, only instead of basing it on distance it bases it on magic attack vs physical), and perhaps just a smidge of Terra's magic. She will have access to Tornado and Holy, at least, and maybe one or two other magic attacks, but she will largely be based around her arrows. As the first character to really use Teleport, ever, I feel this should be incorporated into an attack somehow. That and Pray, but you got me how that works offensively. Perhaps as a windup tech to sap enemy brave and add to her pool the longer you hold in her EX mode?
That said, her EX Mode will be "Purity" and has the effect of adding additional hits to all her bow attacks and making all of her magic guard breaking. It will also grant her glide. Her EX burst will either be one of her TA techs, Twinspell, or something mixing her magic and her archery. I may have to consider this.
EDIT: definitely archery, and along the lines of Play Rough, either with different elemental arrows- in a different arrangement than Shanty's, or with escalating strength arrows, with the cap for a failed being to fire Perseus arrows for two final hits, and the finish for a success to be to fire the Perseus and then form Holy into arrows for 'Holy Ray' for four final hits.
Still needs a name, though. Soul of the Archer? 'of Archery?
Rosa's EX mode causes her clothing and hair to glow, her float wings (which appear when fusileering in midair) to appear at all times, and her longbow to transform into a greatbow.
Her alt Costume is her appearance Re: The After Years. This versions's EX mode gives much the same spiffy effects as her regular.
Mannikin is 'Spurious Fletcher', mayhaps?
Also, thought on Tifa's Alt EX name "The gloves are off!" Visual effects are missing gloves, duh, plus Mako glow on fists.