I would do a couple of things - I would try to package Holliday and Barmes for Hanley (he's really heating up, so it could be too late, but it's worth a try) to feel him out. Since he "really" wants him, this could be a deal that gets done in your favor as I think you're selling high on Barmes, upgrading a starter and freeing up a roster spot.
If that doesn't work, I think you could go for a package deal where you get Billingsley and a throw-in of some sort for Holliday (and a throw-in, maybe?). Upgrading your SPs a bit would certainly help your cause and I think you can use this guy's desire to own the under-performing Holliday against him...
Thanks for the PM BTW- are you a Can of Corn listener, by chance?
Lemme know how things turn out, or if you need any future input this deal