Only issues I've ever found is:
1) Breaks when it uses 30 points to cancel task, so must do it manually.
2) Ice giants task gets stuck after using fairy ring to mudskipper point and walks along the wall of the mountain toward the entrance.
Things that can be improved on:
1) Bones to Peaches - If you have no food, inventory is full of bones and your HP runs lower than 55% or whatever it is set at, it will teleport, even though you have a full inventory of bones. IE: Will only use bones to peaches if you are not in combat.
2) Multiway Combat - If you drink a potion, or loot an item, you will not attack the NPC that you were previously targetting. This can be a serious problem with dagganoth tasks as there are literally 50 of them in the room and when you get one down to low hp and then you drink/eat and target a new one, it makes the task a whole lot longer.
Good luck.