I'll add to my previous comments.

Hoods:

Not many hoods actually turn with the head. Surprisingly, one of the best examples is on the Teva eVent jacket. Some stretch in the back of the neck area is also good for quickly lowering the hood without having to loosen all the adjustements. Also, many hoods have decidedly floppy brims. Arc'Teryx is probably the best of the North American-designed brands, but I much prefer the UK tradition of having a wire stiffened brim.

Cuffs:

The recent trend to eliminate elastic from cuffs produces a lighter, more durable, and quicker drying garment, but it also makes for a looser seal. The move to hard Velcro tabs makes it easier to grab the adjuster, and should be continued. My biggest complaint with most jackets is that the cuff openings aren't wide enough to provide effective ventilation--or allow for one to push the cuffs up to the elbows.

Chest Pockets:

Having large pockets with wide openings is essential, but little thought seems to be given to how easy they are to open/close when the wearer is seated--the material billows out, forcing the zipper to take a curved shape away from the body. The best chest pocket design I know of is found on some Arc'Teryx jackets and the old Patagonia Torre: straight zips into pleated pockets. The pleats allow for expansion of the pocket without using excess fabric.

Drawcords:

I vastly prefer hem and hood adjustments that are accessed through the pockets, leaving no cords to whap you in the face or get caught on ice axes, ski poles, or chairlifts. The foam adjusters that Patagonia uses on hood drawcords are brilliant--light weight, soft, and with no moving parts to break, but still easy to use.

Welded (More Precisely Glued) Seams:

Should be encouraged--they make the garments lighter, stronger, sleeker, and probably more waterproof.

Fabric Reinforcements:

Many times, the heavier fabric meant to increase durability isn't positioned correctly--for example, it doesn't cover your elbow when your arm is fully flexed.

Velcro:

Older jackets used too much of it. Marmot parkas had immensely wide strips on the cuffs that would always catch on the Velcro of the main zipper flaps. A friend of mine with long hair removed all the Velcro from the main zipper flap of her older Patagonia Storm Jacket--that full length strip was always catching on her hair. The trend to recessed Velcro (such as used by Patagonia) is nice.

Then there are some recent trends that I like:

Heated Jackets.

People pointed out the obscenely high price of the TNF/Polartec electrically heated soft shell, but I think it made a lot of sense for one-day activities such as ice climbing or downhill skiing. What's needed is to bring the cost down while ensuring that the heating strands and battery attachment remain durable.

Reflective/Glow in the Dark Fabrics.

Patagonia once had some jackets that had reflective patches that were basically the same color as the rest of the jacket during the day, but became reflective when hit by a light. And didn't Marmot make a jacket that glowed in the dark? Such a capability might seem weird, but the ability to been seen is very useful for night bike riding or after dark rescues.

Game Pouches/Big Back Pockets.

One of the great features of the old Sierra Designs 60/40 parka was the big pocket in the back that allowed you to store a lot of junk between the liner and the exterior of the jacket--often times eliminating the need to wear a pack. The trick here would be to make it so the two layers didn't inhibit breathability and ensuring that the opening was waterproof.

Velcro Accessory Attachments.

You may have noticed that a lot of military outerwear now features Velcro patches all over the place to attach nametags, unit patches, etc. (check the listing for Patagonia military windshirts on eBay for an example). What if your jacket had that so that when you want pockets, you could have them (like a clear pocket on the sleeve to hold a ski pass), then take them off when they're redundant.

Recyclable Materials.

Not only make more stuff out of recycled material, but make sure that you have a process to get the material back from the user to the recycling plant.

For the Future.

How about clothing that could change color (I believe the military is experimenting with this now)? Bright orange when you're in a white out, a muted green when you want to be visually quiet.

Or radical phase change barriers that reacted instantly to changes in temperature/humidty? The pores would open extremely wide for breathability, or could shut down to next to nothing for windproofness/rain protection. Maybe this could be manually over-ridden with a user operated control.

Then what if you could have a garment that had two or more pieces that could be mixed and matched. Let's say a very durable outer, a lighter but still windproof outer, and a WP/B liner. You could then have two softshells and two hardshells with just three pieces. I'd try to find a way to attach the liner in a way that didn't require zippers, Velcro, or snaps--perhaps a temporary adhesive that would make the liner fit as well (and as close) as the tricot scrim on three layer jackets does today.

How about WP/B barriers that use something other than Silicone, Teflon, or Poly this and that? Enzymes perhaps?

And maybe self-healing materials. If the garment is cut or abraded, it would grow back. Or you could dial in the fabric thickness you wanted (for abrasion resistance let's say), and then rub it off until next time. Or when you're terribly hot, slice a new vent and then close it up whenever you want.