Nice to see another in FIW in 15 mm. Curious choice to go with sabot basing in 15 mm; don't see that often (well, I haven't). I went with 3 abreast for regular linear types and 3 scattered for more irregular types like CdB, Rangers, and natives.
Keep it up and let us know how it all goes - and don't let them go this time. If the rules you try don't work there are many out there to replace them.