Scrawny,
Direct reply to your suggestions, hopefully not hijacking the thread
ARM POCKET - Pen pockets only: a pocket under the pen pocket gets bulky, and can pull the sleeve around. The weight of a leatherman or mini maglight would certainly distort the sleeve of a jacket, IMO.
COLLAR - As per the Mk3. Ski jacket collars get too bulky, & I've flown in plenty of different types of ski jacket! No hideaway hood in the collar, but fold away down the back of the jacket, as per Mk3. Or a zip pocket in the back of the jacket with a removable hood, as in Karbon ski jackets.
EPAULETTES - If needed, as per your suggestion
LEFT CHEST ID POCKET - No thanks
RIGHT CHEST POCKET - Yes, especially if able to be accessed with the jacket zipped closed
BOTTOM POCKETS - Not sure about the fleece lining, are you talking about extra pockets on the side of the jacket, low down on the side seam? If so, good idea. All pockets should have zips, to secure against loose items falling out.
CUFFS - Agree, but very important to get the orientation of the cuff right, so the seam doesn't catch on switches, etc.
MAIN ZIP - Agree, but as with others commenting here, the Mk3 buttons are easily done up when wearing gloves. The zip should be able to be unzipped from the bottom as well as the top, and should have a large tab, easily operated with flying gloves on.
RIGHT ARM FREQUENCY POCKET - No thanks.
PIT ZIPS - ???? not sure what they are
STRETCH MATERIAL - not sure whether this is necessary with a properly cut jacket, eg Mk3. Most overhead switches don't need that much of a reach, anyway.
FABRIC - Hi vis materials will create a problem with reflections in the cockpit, both from the instruments, and from the perspex: especially at night. Not a Good Thing. Waterproof, breathable, hard wearing, non flammable and light weight fabric, in a selection of colours, mostly dark. Hides the grease and oil stains from preflights
ZIP IN FLEECE - again, not sure, but my preference would be no. Ski jackets with zip in fleeces are inordinately bulky/heavy with them in, and loose and a bad fit with the fleece removed. The Mk3 has a thin perforated lining designed 30+ years ago, something more modern would suffice.
ELBOW PATCH - Not needed in a cockpit, I'd have thought. Where are all these pilots leaning to wear out their elbows
INNER ZIP POCKET - Yes, never have too many pockets
Thanks again for your efforts, no doubt there'll be a PPRuNe special edition when all this gets onto the market
Add on thought - looking at a couple of ski jackets, one very useful addition to this year's kit is a pocket in the lower arm, on the left sleeve, large enough for a mobile phone/wallet. Just above the velcro fastener, it is ideal for access when flying, with a zip neatly hidden by the seam of the arm.