(Before I get any Replies about "muh the procedure of canonization", this is only a hypothetical and a fun little thread)
I would Personally choose Reginald Garriou-Lagrange OP.
Not only would Lagrange be a leading figures in the Neo-Thomistic movement ,who rejuvenated Thomism in the modern west, but he would be a staunch Anti-Modernist, Lagrange would fiercely teach St Pius X encyclical Pascendi Dominici gregis and he would see it reconfirmed in Pius XII's Humani generis.
Lagrange Piety as an OP and his Faithfulness to a Traditional Eternal Rome should be forever remembered.
I get it, but canonization requires not just good theology but also heroic sanctity, so one would have to look into his personal life very deeply, obtain the necessary miracles, etc. ... perhaps you could start by asking his intercession for some miraculous cause.
Of course, it's quite clear that this is precisely what the Conciliar Church has done, use canonization for political reasons. As even Michael Matt admitted, Roncalli and Montini were not canonized on account of heroic virtue and sanctity but because they were attempting to endorse and "canonize", as it were, Vatican II itself.
But I guess it would be true of all these suggestions, where we add "... assuming that an investigation finds personal sanctity and heroic virtue".