Talking of texture...
I had some noise patched through a VCA and then being filtered by the T-Networks ADDAC103 a while back, varying the level on the VCA to control volume to a fairly low level you can get static or something akin to Record crackle out of it, I'm assuming other filters will do this as well as the T-Networks but I've not tried. It was a nice background element to play with or just tweak occasionally and bring in and you and sweep / delicately ride the control on the 103.
Enjoy your spare HP, don't rush to fill every last space, this is not like filling sticker books. Resist the urge to 'complete' your rack, its never complete so just relax.