Little Mac looks like he's horrible. A character with horrible air game is 50% crippled, no matter how good his ground game is. His air game is terrible.
Greninja seems really fast but I don't think he is overpowered, he is just a good character with less flaws than the others (which is pretty much the same with every smash game). To add onto that, the meteor d-air goes straight down and with brawl air dodges it won't be as threatening
Rosalina is a huge target, I think that will make here less useful than she would otherwise. She could be interesting but Luma might be more difficult to use effectively because iirc it moves around on it's own in whatever direction it wants when it is away from you. I don't know the mechanics of the Luma enough to be sure, but she isn't OP.
Mega Man looks like he doesn't have many good moves tbh so I don't think he is overpowered, he seems to be a hit and run character using his mega buster to get in, smack the opponent then get the fuck out of there.
Greninja seems really fast but I don't think he is overpowered, he is just a good character with less flaws than the others (which is pretty much the same with every smash game). To add onto that, the meteor d-air goes straight down and with brawl air dodges it won't be as threatening
Rosalina is a huge target, I think that will make here less useful than she would otherwise. She could be interesting but Luma might be more difficult to use effectively because iirc it moves around on it's own in whatever direction it wants when it is away from you. I don't know the mechanics of the Luma enough to be sure, but she isn't OP.
Mega Man looks like he doesn't have many good moves tbh so I don't think he is overpowered, he seems to be a hit and run character using his mega buster to get in, smack the opponent then get the fuck out of there.