What characteristics make a good film for this technique?

A LOOOOOOOOOOOOONG Straight line, and a high Dmax.

Foto Import published many film and developer combinations which should help you cut through the infinite combinations.

I think this is a wonderful combination:



Here is another:



HP5 will be good, but I don't think you can do it with TXP. I've tried TXP in 220
with dilute XTOL and minimal agitation, and got to an almost Normal curve,
but it is almost all-toe and no shoulder, and your best friend on a soft, overcast day.