~ bit late to the game because I've been out all day, and had to sleep ;P ~
When has any character been free for any fighting game? Marie Rose isn't disc locked content, they're literally updating the game for her. So in my eyes, it's fine to place a price on her.
BlazBlue ~ Had 3 DLC characters, all were pay to play. The game had to be updated for them to be added.
MvC ~ Had DLC characters, all were also pay to play. I don't know if they were disc locked though? so I'm not gonna say anything about that.
TTT2 ~ Didn't have DLC characters. All characters in that game were available from the get go, no extra effort went into them creating the characters that were eventually unlocked for all people to play. The characters you got through pre-ordering the game weren't DLC- they were just locked content that was unlocked early for people who pre-ordered the game. This is the route capcom should have took- but whatever.
SFxT ~ Had DLC character, you had to pay for BUT they were on the game as locked content... see, now this is wrong in my eyes. You're paying for the game- if the content is on the disc you have paid for, this isn't entirely fair. You've bought the game as it is- and all content on that disc should be available for free.
I'm not sure if there are others, so I'm not going to go on- but there is NOTHING wrong with them placing a price on Marie Rose for that reason. She isn't disc locked content, she was something created after the games release. They put extra time into her- beyond the time they spent making the game.
Also, I don't see how having DLC characters affects the games balance... you can still get into training against her through the online lobbies... =\ using a character shouldn't affect your ability to VS them with this option. Or you can set the in game details through placing the move details on... so I don't get how this affects the games balance.. but that's just me.