And I also thought of introducing the arc where Jonathan Parker Harrison, one of Ruby's rogues, ends up helping Gary and Ana, and decided that would happen because of a second otherwise-combo of Ruby's entire rogue gallery (this taking place well after the first attempted team-up failed miserably): the seven survivors would serve as his, Hannah, and Sally's opponents, with Endless (the organizer of this group) personally supervising the assault.
D.D. and Whitney would have to deal with an initial trap of Mac Rose Sox, which later would be revealed to be him along-side the formidable Master Azev and Queen Edna...along with her entire legion.
Ruby would be with Dale (and Dion), fighting Black Lightning, Lord Deathbrinkdoomkiller and his legions, plus Damon the Destroyer, with them all showing incredibly above-par tactics.
And in a final group, Vili would be with Amy and Herald, them dealing with the combined might of Paul Tristan Reagan Geist, Marcus the Murderer, Saul the Seller (plus Saul's demon horde), General Aora, and his legions of doom.
In short, the first villain team-up was when there were less on the Ruby Gang, but it wasn't every villain, Ruby saw it coming and had planned for it, outsmarting them and destroying them slowly, also having the help of the Mole in the Ruby Gang undergoing a HeelFaceTurn to become a Reverse Mole. Plus it was just them fighting loosely, all as individuals, not really as a group.
In this second villain team-up, organized by Endless, Endless gave each villain an incentive to work with the others in destroying the Ruby Gang utterly, so they not only teamed up, but brought everything they had at their disposal rather than holding anything back. One villain bringing everything is respectable enough--all of them bringing everything is something even the Ruby Gang struggles to handle, especially since they're split into four groups, all scattered across the city rather than (as in the case of the first villain teamup) all together.
Jonathan helping turns the tides, but him being him, it's not without its costs. Plus, all that fighting isn't without repercussions; the city is absolutely devastated, and the villains are very much still holding the incentive to actively antagonize the heroes, rather than simply having the heroes get in the way of their plans. (Basically, it revolves around Endless revealing a secret about Riders and how Riders can, theoretically, be harvested...something most of the villains hold great interest in, for various different reasons.)
An all-around dark arc, but one I can't wait to get around to, since it's the point where the powers of the heroes really start to take off, out of sheer necessity. (Villains, generally, power up slower than the heroes--Endless sparks a change which makes them begin to power up just as much, if not moreso, than the heroes, and also get more creative in ways to subvert the heroes' powers.) A second unification of The Ruby Gang, in essence, to bring them together and show them how much they need to fight.