This. There *are* TO level exploits possible- you can loop summons with all of their points in Affects Others effects to (temporarily) bootstrap yourself towards infinite pp, you can use Remote Sensing and Perception range powers to kill everything from your impenetrable HQ, you can do absolutely stupid stuff with Contagious powers and random bystanders, you can have a Triggered power with a dozen+ iterations all triggering on, say, "target affected by this power", you can abuse the **** out of arrays by pure RAW, you can do similar stupidity with Metamorph...
The thing is that it's easy to tell that someone is going nuts, unlike looking at a D&D build. As long as no-one goes into clear TO range, optimization tends towards the horizontal- squeezing more effects out of your points. Just make sure no one traded off more than, oh, 50% Pl, and that everyone has full defenses and an offensive power with at least one +1/rank extra (discounting Ranged) and things should work out generally okay.