Over at Dave Armstrong's facebook page, he wants to issue a real alternative to the phrase "radtrad." Now I think a lot of the terms he uses are a bit silly and sound goofy, but maybe someone else has a better idea for him.
As for me, I know he rejects the idea, but I think here's the best way to handle this going forward. Call it the Auctorem Fidei approach. To modern ears, this is just some obscure Latin.
That is a shame. For centuries, Auctorem Fidei was one of the central papal documents of Catholic Orthodoxy, especially in the battles against the errors of what we now call Jansenism. The document condemned the acts and tendencies of the Jansenist Council of Pistoria. It took 85 propositions the Council put forth, and condemned them with varying degrees of severity. Even had some bonus points for creative condemnations.
So do that for what you call the "radtrad" position. Take their positions, and list to varying degrees how injurious they are. After that, drop the derogatory name "radtrad"
This has a few benefits:
1.) It is very precise. "Radtrad" means a lot of different things to different people, and even when working with a precise definition, it suffers the same fate as "Neo-Catholic": it inevitably boils down to "crap I don't like." If I say the idea that a lawful ecumenical council of the Church contains heresy is "false, heretical, scandalous and offensive to pious ears", if you don't believe that, you know you aren't guilty of it! (I'm obviously having fun here. The words can be retooled to a more modern audience if you prefer.)
2.) It allows different weighting. Some ideas like the one above are really really bad. Others are not heretical, but they are kinda dumb since they suffer from anachronism in history.
Take the issue of "ambiguity." A lot of people complain about how the Second Vatican Council is "ambiguous", and that is a reason to reject it, or at least ignore it. The standard defense is to scream it isn't ambiguous. I say of course it's ambiguous. So? When Walter Cardinal Casper and Bishop Athanasius Schneider can arrive at a consensus that Vatican II has ambiguity in it, I think it is safe to say Vatican II has ambiguity in it.
This matters less than you think. Conciliar decrees are frequently consensus and compromise positions that are protected by the Spirit from error, but not always guided into saying it perfectly. (Theologians are still arguing over what Trent meant when they talked about the sources of revelation, though depending on who you ask the manner was finally settled with Vatican II.) These things sometimes take centuries to word perfectly, and even then maybe not. So saying the council has ambiguity isn't heretical, but it is for all intents and purposes irrelevant.
3.) You stay focused on the issues. Good people can hold really bad ideas. So go after the ideas. Yes, you lose the power to label people. The sooner you give that up, the better you will be.
If you wanna do this for all Catholics, hey that would work as well. We wouldn't want to think that only those of us who like worshipping in Latin need to have some cobwebs cleaned out. But notice what the document did: nowhere does it add an insulting name to people, yet it still manages to forcefully condemn ideas. This is what the Church has historically done in her documents. Why shouldn't we hold ourselves to the same standard?