Fight starts in the middle of a crowded mall, but they can migrate and the people will almost definately clear out if things get to intense(but their initial presence will likely prevent the fight from being a "quick draw" scenereo involving cutting loose with their powers).
You really think she'd stomp? I mean I know she's a better fighter and such, but Jubilee's powers are easier for her to use without putting non combatants at risk. Not that I think she's unload on Canary or anything, but I could see her getting in enough early shots with it to make the fight interesting at least.
She's young, but she's still been at it for a few years at least. I mean she was like 13 or 14 when she joined the X-Men but was something like 17 when Gen X started wasn't she?