In a pvp environment, when I'm being trained, i cannot turret lightning bolts to regain mana which makes rolling thunder useless. Fulmination is also useless because of how often an ele shaman takes damage.
Puting lightning shield in rolling thunder means that we can keep our charges up and eventually build up a fulmination burst. Sitting on a shaman will still limit burst and spell chains but it will not destroy the mana regen or our fulmination ability.
If the intent for fulmination was to be an ability shaman can use to punish people who left the shaman alone, then do not allow lightning shield to generate more charges and at least elemental will be one step closer to having a steady mana regen in pvp.
These changes would have very minimal effect on pve but substantially fix elemental's mana concerns in pvp. If this idea was already brought up, I apologize, I have not seen it.