In that Genesis arc, Darkseid had a platform which taps into the power of the Godwave or something akin to that. So he probably used it to freeze Ares (and literally required all sentient beings in all creation to ultimately defeat Ares). Well, that, or y'know, Darkseid froze a power which is quite literally the multiversal big bang in reverse, without breaking a sweat (seems legit). At least that's what the Source was considered in that arc and confirmed by the editors later in Takion's 7-issue solo; this is important since the Source's status is somewhat inconsistent (personally, i think the best definition for is that it's the energy that binds everything in the universe/multiverse, that's at least consistent with what was said pre and post crisis)
Besides, the Wonder Woman arc called Godwar established that no one really can control the power of the Godwave, even Cronus (who unlike Ares, actually has potential universal power, since he conquered all creaiton under his own power).
And apart from that, having the "Godwave" doesn't mean much when every pantheon possesses a portion of it. In Wonder Woman v2 #152, the greek pantheon grants Diana "The Godwave":
...She never did anything impressive. Point is, there's no telling how much of the godwave Ares possessed, there's indication that he possessed a great amount of it, but no confirmation he had it in full.
Depends on what you mean by "skyfather". I wouldn't put neither Darkseid nor Highfather on Odin's level, but they certainly have better feats than a skyfather like Zeus (Highfather's feats are the best in the pre-crisis era though, which are still canon since Kirby's pre-crisis trilogy was referenced a dozen times in post-crisis stories).
He has universal-level of implied power. He handled the trimurti just fine, who are the supreme deities of the hindu pantheon. But most importantly we have an encyclopedia saying that he became the lord of "all creation" and saying that he possesses nigh-omnipotent power:
There's a Wonder Woman: Secret Origins issue which tells the whole Greek myth story of Cronus being born of Uranus whom he murdered, and eventually gets defeated by his three sons who also had help, and it says that his rule interwove "all creation" as well:
Meaning he still isn't at full power. But yeah, i already did admit (or at least implied) that Ares' was the greater portion, obviously.
Okay? You're telling me what you read in the comic, that's fine, and im telling you what i read from it. So:
what tells you that Darkseid didn't use that platform of his, which is designed to tap into the power of the source (Godwave), instead of his personal power? Especially given that he didn't break a sweat while doing so? On top of that, The Source in that arc was portrayed as being an ultimate power. It was multiversal and the Spectre tie-in even indicated it's the same thing as "God". So i doubt that Darkseid could affect something like that. It's also established in that same arc, that Darkseid's power is only a fraction of it.
Not to mention that it's very hard, if not impossible, to control it, so that also should be taken into account.