I think Laxus would lose against Jura, elementwise as stated so many times before, regardless of his strength. But I remember a few statements/situations:
Erza---> many times told she could easily be a 10WS, first pairing with Jose after taking enormous dmg, and him acknowledging her.
2nd: After her "death" when she's dreaming in etherion she sees a vision of a future where she's dead, and the people of the council give her a honorable 10WS seat.
3rd: no matter how much fodder those monsters were, she prooved strength and willpower.
4th: Why she would be able to defeat/matchup against Jura? Well, she has to have an armor that halves earth magic, so there you have it.
Gildartz---> stated by Makarov dat in terms of magic Jura could easily compare to him
I kinda think Gray will destroy Rufus, and the main fight will be Gray vs. Leon
Laxus will deal with Orga, and I'm not sure how that will turn out (since he's a god slayer) but I'm pretty sure Laxus will be victorious. There's a chance he will move on to fight Jura or Cheria, dunno.
Erza will definitely get Minerva, and after that (depending on Minervas real strength) she will move on Jura.
Gajeel will probably defeat both dragon slayers, or so I hope. I mean, it seems logical.
Juvia might go against Cheria, or Kagura. Or even Minerva, I don't know. Because I kinda think Erza would also fight against Kagura or the cat woman, there's so many opponents with a connection to Erza. I can't put Juvia anywhere here against ST, so I guess she'll be the main force against LS and MH...
We have clear matchups with ST, but we still dont know how the other big fish are gonna fight it.
EDIT: It just came to mind, where is Jellal and the gang? O.O He hasn't been seen in a chapter since she met that girl. And where is she, also? I see some nasty shiat happening predate of the "apocalypse"