Mana problems

So with the RAF thing going on, I finally decided to pick multiboxing back up and created a new account to level up a few alts while waiting for wotlk to come out. The combo I've been working on a lot lately is a druid/shaman combo. The problem I am finding is that the druid goes oom fast. Very fast. The faster cast time and higher mana cost of wrath over lightning bolt means my druid has to drink every other mob or so while my shaman rarely does (mostly since he gets the extra regen time while the druid drinks). It just seems every level the difference gets worse and the shaman gets more mana effeciency talents and the druid stacks damage talents. So I am starting to think about just making the druid feral and having him tank while the shaman blows stuff up. This brought me to two questions;

1. Are there any glaring setbacks to doing this I am not aware of?

2. Is there a / command to stop following that doesn't involve moving? Like I want my shaman to stop following and start casting when I have my druid charge.

I'm running a 2 mage team with a druid tank.

Althought slightly different, I've found that I really dont need to worry about keeping the mages back.

I used to just hit the back arrow when the druid charged, but found the druid held enough aggro on a single target after the charge not to worry about it. If the mages pull aggro I taunt and it gets the mob right back on me. I also tend to arcane explosion if there are a few so the mages being back a bit hampered me.

With the shaman you can cast a lightning bolt within melee range and wont suffer from interrupts if the druid has aggro. You can also (if you have it, drop fire nova totems).

At 43/44 my druid tank is doing a fair old bit of damage himself.

Also if the mob you are going up against is a squishy you can use cat form.

Feral is a better choice imo.

As for the stop follow, you could make a macro which does /sit then /cast?
Not sure if it would work, can't check as I'm at work .. "working" ... but it's worth a shot.

Alternatively, whatever button you have bound for charge on druid, make it press forward on your shaman. Viola, it's stopped.
Then all you'd have to do is mash lightningbolt /druid attack key!