The Ex3 rules are relatively straightforward, actually, except for the amazingly stupid names. Well, and the amazingly ugly art. First time I see a non-free PDF where I have to actively disregard the art, because man, is that ugly
Back to combat, if they had named "withering attacks" as "beats" or simply "preparation actions", it would have been much easier to digest, and mostly make sense.
I don't find Scion all that bad. I've run plenty of games of it, and while it does need some rules tweaks in places, there's nothing a decent GM can't work around. I played a tabletop campaign from start up to Legend 8 demigods, and we ran into very few problems.
Then you're either a much better GM than me, much less mechanically inclined, had amazing luck with your players, or a combination of those.
I'm going to hope you're simply a much better GM than me, because that would be the best for any game we play