Resto Staff users in groups seem to have unlimited ability to cast and heal. Perhaps some ramping costs would make PvP more enjoyable for players encountering large groups and, make healers feel more valuable and skilled when making casting decisions.
"O divine art of subtlety and secrecy!
Through you we learn to be invisible, through you inaudible; and hence we can hold the enemy’s fate in our hands.” – Ch. VI, v. 8-9. — Master Sun Tzu
"You haven't beaten me you've sacrificed sure footing for a killing stroke." — Ra's al Ghul
He who is prudent and lies in wait for an enemy who is not, will be victorious — Master Sun Tzu
LoS