Sakurai will get "bias" no matter what. The problem is that the choices he'll make will be debated, no matter what. It's a lose-lose scenario.
- If he picks Medusa, people will complain that he went with the boring villain and not the edge, super-cool one. But, for the record, I view Hades as super-lame, though I do respect Hades fans, so I won't lie by saying that this is the lesser of two evils, IMO.
- If he picks Hades, he'll catch hell for picking his own creation over a character that has more involvement in the canon.
- If he puts BOTH in, people will complain about him going overboard, even if people get both the traditionalist & the wild and crazy evil god.
- If he doesn't do either one... Dark Pit should stick to being the character some fans wished they had a voodoo doll of.
So, you can see the dilenma.
I'm also curious as to what Medusa's Guidance will be. I'm hoping Medusa takes over for Palutena and Viridi and simply makes it a threat to Pit, but more likely than not, she'll eventually be asked why she helped them in the end, and Medusa reluctantly states that she grew tired of being revived and manipulated, and wanted her misery to end (I'm guessing her involvement in Smash Bros. might have been a reward by Palutena for that, which the Goddess of Light would joke about). She's an evil goddess, but as we all know, she's an honest one.
And, as for Boxing Ring title... Queen of the Underworld Army. Plain and simple.