Sorry to return to topic....
Personally there's a few ways to look at the addition of a new character :
1) Balanced? All the characters have to have something that makes them worth using, outside of tits. Sure, some female character who is simply eye candy would look nice, but why waste time on that when after the 1st 15 minutes no one would care because she sucks?
2) Story : Would if makes sense to even attempt to have a fight between a large purple alien and some squeejey kid on the street?
3) Time. If you only have so much time you'd like to finish it in, wouldn't the time be better spent on something more useful than a floating pair of breasts? Some would argue opposite me, but it seems that I take a stance to be practical..
By my logic, there can be only one. The android. Fits the story, people see her as a valid choice and though tricky to balance, probably worth it.
Let's break the character down shall we?
She is an android. She doesn't require energy. This is the first major hurdle.
Lets look at a reference *watches an episode* Hrm, she has no really powerful beam attacks and no turbo, she has no mass nuking capability. How ever she spends most of her time engaged in melee combat not particularly firing anything flashy, just a good solid beating. She is un detectable on radar, minor hurdle.
We are left with the following :
Her beam attacks are negligable.
She can fly for free - As can Cell.
She is melee centric
She actually can sneak up on people.
Vs
Her beam attacks could be fairly constant.
She can teleport any time she wants
She's rather outclassed when everyone else gets their upgrades, but that's more of a player issue.
She is off the Radar, making it very easy for people to just run the hell away.
Solutions :
Teleporting requires energy like everyone else, how ever she would regenerate quicker (since she can't uh...press E) than the others. This keeps the entire scenario of teleporting the hell away, throw off some gen blasts and teleport like hell to get away from everyone , out of the question. She can teleport, just not infinitely. Since she's off the radar she can very well hide for a few seconds to regain power.
She is physically weaker than her opponents in most cases, so I feel the fact that she is off the radar is justified. Since she doesn't have any extremely powerful long range attacks, it's not like she'll suddenly become a sniper.
She is, after all, melee centric. There for the only issue is with the "infinite power" throwing, but really, it doesn't do that much in comparison to a combo or just a regular beat down.
She doesn't transform : Do you plan to be attempting to PS with her? I'd hope not. Other than that she loses a little bit of damage if she gives them time to trans.
As for a signature (if her Ki and lack of radar signature werent enough) I was thinking on something that isn't directly related, but instead was some what more theoretical.
As she lays down beatings, she takes a bit of Ki away from her victims with her melee shots. Why this? Why attempt to take away the ki? Lets set up a hypothetical.
She's fighting an Upped vegita player. Not only is she losing fire power wise, but PL wise too. What counters that uberness that blonde hair brings? Knocking him out of the transformation via ki drain. Yeah, it sounds like a horrible idea because it leaves them defenseless...but that's the point. She brings them down to her level.
Thus ends my thoughts on the subject.