Why not set a 999 cap and rebalance their damage multipliers so they don't do crazy wack damage from beginning to end. I know a few patches ago summon AP was changed to scale up to it's cap'd value. That just  might be the first step in a plan to make fully scalable summon AP. But it kinda felt like someone had to post this thread just to make sure it's actually happening. Right now summon damage kind of becomes obsolete the moment you hit endgame DP mobs and players.