For reference, the current Elders:
http://elementscommunity.org/wiki/Level_3Elders were specifically updated to have more focused and consistent synergies, as well as slightly combating the trend of rushing them at the time. Zanz probably knew it wouldn't change the fact that rushing them is the most profitable strategy, but it does help rushes more to have a little bit of control. What he managed to do is create powerful, but slow decks. The old Elders were mostly just slow. Once the current ones get set up, the average unupped deck gets utterly steamrolled by them. The solution is to not give them the time to set up, but their defence became more multi-faceted and generally speaking more effective.
The FFQ deck is the most striking example. It went from the worst Elder to the best by trimming useless fat, adding the obvious 4 Hopes, an incredible 6 Bonds, a consistent 3 OE's and 3 Shockwaves to compensate for low speed of setup, and best of all its quanta became well balanced. It now gets fast
and enough
for a fast setup and the strongest setup of all Elders if you make the mistake of giving it the time. This is reflected by giving basically all decks the most losses during TTW testing. When I tested the Healbow a whole while back, it was the only Elder to give me any losses. 2 losses in 200 games.
The Monoaether Elder was just a matter of time, really. It is definitely the second best Elder, and Zanz knew it'd be a headache no matter how he did it. 5 Dims and 15 pillars in a 42-card deck is a generous way of giving new players a chance, but usually it will still just show them the power of Dims, Lobo, Mindgate, Phase Spiders and Phase Dragons.
Lightnings slow down the farmer if the Elder gets a low quanta draw and decimates the likes of non-Phoenix Immo decks, the addition of PU's to the Elders' decent speed makes racing against the Elder impossible if you're running a Golem or buff deck where one or two of your creatures are going to be super-powerful, and Silences sometimes just gives you the middle finger when you thought you'd win by Exploding that last Dim Shield or play your own defence against the immortal onslaught. All in all, unupped non-Pulvy users (because SoFo's do bow to Lobo/Lightnings a lot of the time) are lucky Zanz gave this Elder only 15 pillars and made the deck so big. With its tendency to low quanta draws and AI stupidity of not conserving quanta for Dims on occasion, it's a LOT less dangerous and annoying than it could be.
The rest of the Elders tend to have tons and tons of CC to combat mindless rushers. The two Elders that use Gravity as a major element are the exceptions (Pharaoh deck only splashes it); though the Earth/Gravity one has the potential for tons of CC with its Auburn Nymph, its defences are incredibly slow. This and the Gravity Elder with Sparks are the weakest ones. The Light/Time one, while it has annoying RT's, relies mostly on Sundials for defence. I'm pretty happy it doesn't have Eternities.. but it's actually the fastest Elder. I was kind of flabbergasted the first time it rushed me in 7 turns. I never thought I'd see the day that an Elder had 5 Pandemoniums though, honestly. I'm just glad Zanz wasn't mean enough to give it Bone Walls too.
The Rainbow Elder is kind of funny because it's like Rainbow Jr. with splashed denial. Lots of control, decent speed and a bit of drawing power. One useless Precog in a 40-card deck, but the combination of Squid, Toadie, Demon and Fog is the bane of many control-less rushes.
I've always liked talking about the AI. Used to write so much for the FG articles on the ol' Wiki :>