Having now looked at the Slop Contracts patterns and finishing up an outfit based (in cut only, not color) on that pattern, I feel it's a great starting point for new comers into the time period. I feel it really nails down the fit and cut of the period. You can't go wrong basing your pattern off of that one. Besides we are talking about a minimum garb standard. Not absolutely the only thing we find acceptable. Once you get the feel for that you can expand and move on to other, fancier treatments to the outfit. Perhaps a different pattern, although I think the Slops contract has it down pretty good.
Just my 2 cents anyways and we're not in twill. So I digress.