Babee, I don't know if this will help you or not, but here goes. I make pillows for alot of people and they all have different requests. I do alot of upholstery work. If you get a piiece of foam, say 1-1/2 to 2" thick and put the batting around it that should make it firm. And since you don't want it to be poofy that will help keep that down.
cut the foam smaller then the cushion itself so you can put the batting all around it. A good way to cut foam is to use an electric knife.
The foam gives it the firmess and you still have the batting to make it soft. I hope this helps.
Barb