The London Lounge

Are pinstripe suitings almost always in a twill weave? I would like to find something in plain weave for the warmer months ahead.

Holland and Sherry's Crispaire Fresco book has several striped cloths, some subdued and some very festive, in a 9.5 / 10 ounce weight. I think they'd be a good place to start.

I have seen that H&S and Minnis' fresco books. Anything else besides fresco?

You can get pinstripes in any weave, whether it be Fresco, Tropical, Worsted (I assume this is what you meant by twill?) or Flannel. I have just taken delivery of a lovely white pinstripe on navy in a Smith & Co S120s lightweight tropical. A bit early for summer, but there is always hope...