So since a lot of people think that macroing and/or afking with Sorcerers and Necromancers, I think those classes summons need a major rework to counter this. I suggest the following:
Necromancer:
Give every summon (Skull Archer, Skeleton Soldier, Shoggoth) the same incurable decay debuff that Bokors zombies have. They are made from corpse/carrion, so why should they not decay at all while Bokors zombies do decay? This makes no sense at all. To make it fair, the CD time of Create Shoggoth should be lowered to ~180 seconds so a new one can be summoned once the old one decayed.
Sorcerer:
Ok, since the Sorcerer doesn’t summon from corpses, he’d need another treatment than the Necromancer. I suggest that the summoned Monsters coming from “Summoning” get an attacklimit instead, meaning they will automatically decompose/return to the shadow realm once they have used up all their magic energy that has been put into them during the summoning process. Best would be something between 50 and 60 attacks, which would lead to ± 1 attack per second CD time. This should be sufficient to make the player play the game instead of afk-ing and come back after several hours to check on his silver balance.