I've been thinking about what you could make. I've been considering all the generic things that people tend to have on TaleWorlds threads or forums when they make regiments, and came to these conclusions: most of the stuff they normally involve, you have made. However, I think we've overlooked something major - regiment colours! You could do a regiment colours pack, so get a generic background colour with a British flag in the top left corner, make the green wreath on it with some decoration in, and then do for example the 51st in Roman Numerals (LI), with REGT. underneath it, and from there we can just edit the number and background colour for our own regiment. Sorted. :3
Like this. But in fancy .psd form. Or this (clearer):