I just finished a 4PP using regular fabric, last week!
For me, I look at the size of the print in the fabric.
Small print ... smaller poseys! Larger print ... larger poseys!
The one I just did, was a floral print, not overly large.
So, I cut at 2-1/2" and got a good variety of kaleidoscope effects in the poseys.
For your panels ... If you cut it smallish.... are you going to see any kaleido design form?
Remember, the larger you go, the fewer 4PP you will get, to do your layout.
Good Luck!! ... will look forward to see how yours turn out.