The stand sizes in Regimental Fire and Fury are only listed for 15mm figures. The rules say for 25mm-30mm to increase the stands sizes to 150 percent. Based on that, here are the 28mm scale stand sizes:
Infantry – 3 figures, 1.5" wide by 1 1/8" deep
Cavalry – 2 figures. 1.5" x 1.5" square
Dismounted Cavalry – 2 figures, 1.5" wide by 1 1/8" deep
Artillery – 1 gun and 2-3 crew. 1.5" wide by 2 1/4" deep
Brigade or Artillery leader stand – 1 mounted officer on 1.5" diameter round base.
Division, Corps or Army Leader stand – 2-3 mounted or combination of mounted and dismounted officers on 1.5" round stand.
Brave Colonel stand – 1 mounted or dismounted officer on 1 1/8" round base.
Disordered/Silenced marker, low ammunition marker, damaged gun marker – 1 1/8" round base
Horse Holder marker – 2 1/4" round base
Limber marker – 1.5" wide by 2 5/8" deep base
Ammo Supply Marker – Supply wagon w/2 horse team – 1.5" wide by 3 3/4" deep
Heavy Casualties marker – Ambulance wagon w/2-horse team plus optional stretcher bearers with wounded soldiers – 4.5" round base.
The rules also say you can use different stand sizes than listed above as long as you keep the sizes standard for all of your armies.
takes a look at flexible roads made from long-lasting flexible resin.