A few things here that could help, especially with instances. put two points in guardian totems. the 2 second cooldown off of grounding totem is amazing with 5 shammys. I've found through experience that most of my dungeon wipes were due to not keeping grounding totems up and then being forced to try and heal through the damage. I also noticed that all your shammys are spec'd identical. You only need totem of wrath on one of them, maybe two if you're worried about someone targeting it down quickly, but since they don't stack, there is really no reason to spec them all for it.

I would also suggest taking some time and farming totem of void ( http://www.wowhead.com/?item=28248 ) for all of your shammys. Especially now that you are 75, you would be able to fly through it. @ L70, it took me about three and half hours to get all 5 of them the void. Then on top of that, you'll likely be revered with Sha'tar and be able to buy the head enchant +22 SP, +14 SH ( http://www.wowhead.com/?item=29191 )

After you reach 80, you might consider getting enchanting on one of them as if you plan on doing solo instances, it makes it very easy to farm mats to enchant your team.