I personally find Kratos to be an easier opponent than Sackboy if only because I fought him enough times to where his attacks became predictable, I'm sure others will agree.
I'll put it in this context too, I find it harder to get to Sackboy to get in a free combo than Kratos, not that it's all that hard for me anyway because I use Jak and Jak's down circle in the air is a great way to close in on Sackboy and at the same time disable any shock pads nearby plus he can't deflect it with his fan because it doesn't count as a projectile so I as well as any other Jak player have an advantage, and I always make sure to destroy any checkpoints Sackboy sets up because I played as Sackboy for a few matches myself so I know how useful the checkpoints can be and I know exactly when the Sackboy player is going to want to use them.
I do not think of Kratos as overpowered. He is one of the most annoying characters because of his easy to hit moves. But as much as players can spam attacks and just get hit after his as well as sending you to the other side of the world, he does not gain much AP. And those attack work because players often are busy with hitting others. And here he comes and chain grabs you (litteraly) and you fly far, far away. But those moves are terribly unsafe. If he hits those like 3 times and then you decide to block it, you can get those 140 AP combos, no biggie.
But yes, make him less annoying. I agree with that completely.