Tom, have fun in Texas!!
I've been shooting 17tn's for quite a long time. 17 Hornet, 17 Bee and 17 Remington,
Sorry to say I've had no experience with the Fireball, The Bee and Hornet have been very good on fox and cats. Fringe hits as usual make you get out the needle and thread.
I've had mixed results with the 17 Remington with 25 grain Hornady HP, V Max and Remington Hp's as far as being easy on soft critters. My experience on fox as almost exclusively been Kit fox so big difference between them and grey's or red's.
Nice thing is that USUALLY if you keep them in the ribs on fox and cats they are pretty eason on fur but you know as well as I do that broadside shots are always nice, they aren't the rule.
In my opinion you might just be on the right track with the slower .224's with tougher bullets. Are you finding that they are not as effective as you would like, too destructive, poor trajectory?
On the other hand, everyone should have several centerfire 17'ns.
