Moersch carbon toner might be worth a try. Not had time to do any real testing with it, but initial impressions are with a low 1+30 dilution, it cools similar to selenium. High dilution above 1+100 it has a subtle warming effect on Fomatone MG Classic, but nothing noticeable with Ilford MGIV FB.
Used on a warmtone paper with the right dilution it might be possible to deepen and cool the shadows and warm up the highlights. Maybe by toning in a low dilution bath until the selenium component has done its work on the blacks, then moving to a water bath which will dilute the carried over toner so the sulphide component warms the highlights.
Ian