For a winter soft shell:

Take the third generation Patagonia Dimension (with the welded seams and no elastic on the cuffs), but use the second generation Dimension fabric (which was heavier and more abrasion resistant than the third generation all poly material). Keep the inner zipped pocket, but also add a drop-in mesh water bottle pocket on the interior. For the hood, use a wire stiffener (as Patagonia once did, and many UK jackets still have).

For a summer waterproof shell:

Take the Arc'Teryx Sirrus SL, but change the material from a PacLite/XCR combo to eVent. Replace the one Napoleon pocket with two mesh-backed full size pockets. Add a wire stiffener to the hood brim.

For an expedition shell:

Take the Patagonia Ice Nine, but make it with Gore Pro Shell and use welded seams. Add a zippered inner pocket to complement the mesh drop-in pocket on the inside. Make the waist drawcord cinch only the front (so there's no cord to rub against a pack). Use the hood adjustment system from the Patagonia Dimension jacket. Add a wire stiffener to the hood brim. Perhaps include D-rings on the sleeves to attach the keeper loops of gloves.

What I don't need: lipstick pockets on the arms, inner powder skirts, hoods that hide away, or anything to do with iPods.

Make sure the pockets are large enough to hold skins or a trade-sized paperback, and that Napoleon pockets are large enough for sunglasses in a case. Test to ensure that the pockets can be opened and closed when you're sitting (surprisingly, many jackets don't have this capability).

Pay attention to the hood design, and especially how it fits over a helmet. Offset the main zipper so that it doesn't chafe your throat.