There's already more than enough characters. Some of the newer ones feel pointless or even boring. Seriously, Young Cricket is so boring. He's got no quirky personality trait like the rest of the cast.
I'd like another character similar to Ashley, some magic user who's lonely but nice...ish. Like, she tries to be nice, but inside she'll probably burst out in anger at any given time.
She and Ashley could probably have some sort of rivalry or not even know about each other at all. This new character couldn't care less if she had friends or not, she just wants to become
the strongest, single most powerful magic user in all of the universe. BUT ---- like Ashley, doesn't get most of her spells right.
I don't want to see new characters at the moment.
I would prefer Nintendo to put their focus & efforts on developing the cast we have already, Especially in the case of characters like Ashley, Penny & Young Cricket who all need some servere character development. Also, this is just a pipedream personally, but I would also love to see some old characters return and maybe even explored a little bit like Vanessa, Bridget or Jamie and James T. But like I said before, it's just a pipedream. (I would love to see Waluigi though.)
(Edit: i steamlined the thing a little bit. just to get my point out better)