We need to fix our broken stuff guys, not be makeing new stuff.
If they developed their new anti magic in a revision, we ought to be able to counter it in one.
We need to address the antimagic. I agree with improving broken stuff in theory, but this is terrible terrible broken stuff. We are throwing a flying machine when they have complete control of the weather and a massive air force. It is doomed twice-over under weight of numbers and environment. Not to mention that its control methods are mysterious and don't really make sense as to how someone can control it when they are not the source of the magic holding it aloft. There is "shoring up your investments" and "sunk cost fallacy". Just because this disaster was supported once, and utterly failed to meet any single one of its design goals, nor even make appreciable progress in the relevant fields, doesn't mean that we should continue to attempt to build a design that is a convenient revision away from being hard-countered. They could revise their wind to flip it upside down, or revise their lightning to cause thermal expansion and blow them up, or revise their tornadoes into gank-teams that shake the thing until the contents are mashed, or revise their ballistae to shoot heavy nets, or revise their mind-reading spell to distract people a little while they are trying to control the minor incarnation of pure chaos that is keeping them from flipping over and falling to their death. Or they could just use the large metal bolt that they already have, with the lucky strike that they already have, to hit the misguided coffin and throw off its balance, once again, causing it to plummet to its doom. Maybe, MAYBE, if the propulsion actually works this time, it might be stable enough to withstand a little turbulence, and hit anything, ever, because 4 thrusts per second is way too messy to aim from, or to survive your head being jostled that much... but with no specific mention of the propulsion being prioritised we can just expect a repeat of the previous turn, until we roll a 5 or something, whatever doesn't count as a "bad roll" to people who don't understand dice.
Currently, our cannons do not work. We need to get our cannons working. That is how we stop making new things and start fixing what we already have.
As for a revision beating a revision? If that were true then this game would be pointless. The actual content of the revision matters. The Keggers revised their antimagic to be useable from their airships, probably by allowing them to specifically mould its shape around sensitive materials. They were already doing things like that ages ago. What we want from a revision is to go from having no defense at all against their antimagic aside from allowing crystals to persist(not be summoned, just persist) in the presence of antimagic, a feat that they could always perform within our own antimagic(which is the large part of how their antimagic is cheathax). Now, instead of hard-countering their antimagic towards one, single material, once it is already in a largely mundane state, we want all of our active magical effects, such as the explosion spells that need to be constantly resummoned over and over again with no mundane fuel or intake in complete contravention of all that is mundane, to be universally functional while within and antimagic field.
Their revision: Change the shape of one friendly spell. This has already been done in more-or less the same way(When they made the clouds bigger), it just needs to be better.
Our revision: Immunity for all of our equipment to a hostile spell. This has already been done in an extremely specific scenario that only affected the entity itself in a specific state when it was basically inert, and the process was mostly centred upon making it inert, now we want it to radiate a field of complete immunity to everything around it in complete contravention to any properties previously displayed in this field. Even our antimagic charms were completely transparent to their antimagic fields but now we are supposed to turn our antimagic-transparent crystals into antimagic conduits without removing their antimagic resistance somehow.
Their revision: Change the shape of one friendly spell.
Our revision: Immunity for all of our equipment to a hostile spell.
Not all revisions are equal.
We need to fix our broken cannons, not be fooling around with ridiculous flying contraptions.
The thing is, anti-magic resistance in a design will just put as back at square 1.
Or we could do the living spell and actually get some theoretical toys to play with that would support our other designs. Like flight computers to stabilise the floating coffin or autoaiming for our cannons.
'Or we could do the mage-slayers and defeat antimagic by killing all the mages that try to use it. A "beat antimagic" design does not have to be purely that with no progress. A revision, on the other hand, pretty much does, has a greatly reduced scope over what it can protect, and can roll badly and just fail with us having no recourse to fix it.