Been thinking of a few things regarding Medusa, if the demo's do infact count towards eligible characters. I've already expressed my interest in her, loving her artistic design, also her being both a female fighter and a villain, add to that an awesome voice that should have more than enough to sample from (and if not, I'm sure there's enough Cree Summer out there to fill in the gaps)
Also, as far as her role, I want her to use her goddess powers and natural abilities in battle, therefore I have come up with an idea of her being a partial trap-user as well as DPS, when she attacks with her snake heads, which she can do for some of her smashes and grabs, it poisons the target, doing damage over time. Most of her special attacks focus on controlling the battlefield, doing damage and keeping herself safe. Here's a couple ideas I have for special moves for her:
N Special: Gorgon's Eye, with a stare, Medusa petrifies her opponent for several seconds, similar to Mewtwo's Disable, but it lasts a second or two longer. It freezes an opponent in place, making the vulnerable for punishment. The one drawback is, while petrified the target is immune to knockback, a nod to the petrification status effect in Kid Icarus: Uprising that increases the target's defense. However, this also means although it's harder to do killing blows on a petrified target, you can also get a bit more damage on them, and possibly set them up for a nasty attack if you time it just right.
F Special: Goddess Claw, Medusa rakes her claws across the area immediately ahead of her with such force she temporarily rends space itself. The attack itself has incredibly short range, but is quite strong, cleaving an opponent and able to KO at mid-levels. Also, the three streaks of red from the claws linger a second or so after the attack, creating a defensive barrier as space repairs itself. The spacial rend can block projectile attacks, giving the move a double usage, as an attack and as a defensive strike. Can be chained very well with Gorgon's Eye for easy damage.
D Special: Summon Reaper, similar to Dedede, Medusa as the goddess of darkness can call upon her minions to aid her in battle, unlike Dedede however, instead of lesser troops Medusa does right for the big guns and summons a Reaper to battle! The Reaper walks calmly from side to side for several seconds, although if they catch an opponent in their sight they will speed up and slash at them insanely (might be able to be done by simply reskinning an enemy from SSE, maybe redead?) The drawback to this move, however, is Medusa can only call one Reaper at a time, similar to how Wario's motorbike worked. Until her Reaper is destroyed or vanishes on it's own, she cannot summon another one.
U Special: Toxic Teleport, Medusa teleports as her recovery, although her overall teleportation range is a bit shorter than Mewtwo's, and she is in helpless state afterwards. However, in exchange when Medusa teleports she leaves behind a nasty surprise, a cloud of toxic gas lasting several seconds that will automatically poison anyone unfortunate enough to come in contact with it, doing damage over time. It can be used as a recovery move, or as a nasty trap, punishing an enemy looking to attack the dark goddess, leaving them only with poison to contend with!
Final Smash: Goddess of Darkness, Medusa disappears and reappears giant-sized in the background, in her full goddess glory. She will sweep once with her right claw, then with her left, before she fires several beams from her eyes that carpet bomb the stage, causing minor explosions. Claw swipes have more KO power but are easier to dodge, whereas the eye lasers are harder to dodge but don't have as much KO power, instead raking up damage for Medusa's return to the battle once her smash is complete.