Your lineup lacks a solid tank, everyone in your team is extremely squishy including your main. Earth element prior to level 55 is support.
when I was leveling my earth to 55 I used this team. Also be sure to have ALL gear and characters maxed out before leveling so you can make things easier on yourself.
As far as talents use
Mystery: the interrupt skill or the knock down skill
Standard: The normal or Konoha Senpu
Chase: Primary lotus
Passive: Pose of duel
Gaara should be a regular on your team . as a sustain tank you'll need him to keep you and your teammates safe.
Kabuto is vital as well. His heals will be good to sustain your team and summoning his dead souls will help absorb some damage from the other team.
Kakashi will be a secondary source of damage, mainly to make combos. His waterclone is also good at taking hits and if youre lucky it will be killed the first turn and you cn do gaara's sand hell and kabutos corpse summoning on turn 1.
Lineup should be: Gaara at the middle of the front row, Kakashi directly behind him and Kabuto directly behind kakashi. Your main will be at the top of the middle row.
You could also replace Kakashi with Neji GNW for better combos and for crowd control purposes.
-This advice is pretty much what I did while leveling my earth main. I used the team I ust recommended besides GNW Neji because he wasn't out yet.