Nerf Summoners Utility, not dmg like Semen said, they're too strong in Olys, if u wanna be loyal to what u have always done in this server (which is do things right, not necesarely official like if it didnt work) find a better balance here in olys for classes like ES (specially this) and maybe DA's (bcoz in this case, i have to agree with JaneDo, they're strong, but its not easy to be strong on DA as u need much more equipment and epics to be a farmer than with ES).
Resuming, Summoners still needs to be stronger in open world, but weaker in OLY, so nerfing skills that doesnt affect the open world pvp (like Summon Pet with increased CD, so that they need to start using their brain and use pet heal, pet recharge etc instead of insta summoning new pet) would make it work imho.