The only drawback I see is that you should compare every pair of CVs for best results, and that grows quadraticly with number of CVs. Of course you can settle for fewer comparisons and not perfect results. But then I'm not sure if you can hit a good ratio of quality and token spend.
1. Set the elo of all CVs to 1000 elo
2. Randomly pair up CVs and compare. Winners gain elo, losers lose elo.
3. Repeat #2 for a few iterations, then remove bottom X% of CVs.
4. Repeat 2-3 until the amount of remaining CVs is small enough to do an exhaustive comparison.
I don't have a mathematical proof, but I suspect that this is a decent cost-effective approximation of comparing every pair (depending on the parameters)
Or compare each one to a reference set? Take 5 resumes of existing employees, rank all candidates against that set, maybe you get some useful level prediction into the bargain