Definitely not. Paradox was relying on a lot of features the YR engine lacks - unit ability buttons, individual queues, separate building methods - and a lot of these will probably never happen in Ares due to obvious reasons - complexity of getting these working.
If and if (I can't stress this if enough) there is a chance to make Paradox happen, my vote would be that it would happen on OpenRA, but even that one lacks a lot of the features. The difference between OpenRA and Ares here though is that OpenRA is a lot more flexible in terms of feature development. I don't say it will happen nor I say that it's possible - I have no idea about 75% of Paradox's plans -, but that probably would be a more feasible choice than Ares. Although even OpenRA would rely on cell-based logics and not complete 3D ones regarding positions and whatnot compared to RA3's 3D engine.
Ares is a pinnacle, but you cannot expect RA3 from it.
I wasn't suggesting that Infinity Realms try to make the mod as they intended to make it for RA3, I was wondering how close they could've got it if they tried to work with the limitations of YR/Ares as opposed to RNA, even if it meant removing some gameplay features like the different build methods (although someone has figured out how to do the Nanocore build method in YR/Ares, which could also potentially be used for the Talon's base on wheels gameplay with some changes of course), the unit secondary abilities (some of which can be argued could do using the unit "deploy" logic) and the multiple queues.
I do agree with you that OpenRA is probably the mod's best shot at ever being finished although I still believe that with YR/Ares they would've gone much farther than with RNA even if it means redoing the gameplay to be more in line with RA2.
Best case scenario for the mod in my opinion is that Infinity Realms' indie shooter Bloodcrusher II ends up becoming a indie superhit on par with something like Rogue Legacy or Fez or Shovel Knight, giving the team enough money to just make Paradox its own original IP. Wouldn't that be awesome? Sure they might need to do some writing around trademarks, renaming a few factions or outright replacing them with some from the Paradox Expanded Universe (fingers crossed for the Imilki Ecumene), and toning down the references to C&C lore but if the core gameplay remains intact I would definitely buy it.
