Who currently in the guild do you think will be the master after (or before if u don't think she'll be after Mokarov) Mariah Jane?

Well, Laxus is Makarov's grandson but he doesn't seem to be interested in being the master. He even said it himself. I would really amor to see Erza become the Master after Makarov. She's very strong and she's a great leader, so I think she'd be a very good Master.

Well Makarov then it was Macao then it was Makarov when he came back from tenrou island then it was guildarts then guildarts gave it back to malarov and then Erza then Erza gave it back to Makarov

Macao