Here's my list, likely to be added to as I think of it and run games:

Weapon Qualities

Summary of Fatigue Rules

All of the Conditions

Summary of Influence and Subtlety

Summary of Social mechanics and Disposition

List of the Specialties available from the Specialty Talent (quick way to know if a character shouldn't know something)

List of skills and skill actions

Summary of Clues and Leads

List of combat actions

Summary of Exploration Encounters

Hit locations

Personalities for NPCs

List of cover

Combat modifiers

PRINTOUTS OF THE WOUND TABLES

What I do NOT need

A list of all the weapons (I know this has been in every 40k GM screen but its frankly a waste of space. It becomes out of date by the time the first supplement book comes out, and given how every npc has a weapon profile, the players all have spots on their sheets for weapon profiles, and the fact that improvising an NPC for combat is probably going to require a look at the book and preparation anyway, I think the weapons tables could be taken out to free up room for more useful information on running the game.

What does everyone else think?

Very good. I'd second having the wound results too, I never liked that they weren't on the old screens.

Same goes for the weapons. Before long the list became pretty useless as new books added weapons.

Ultimately just having every table that is used regularly and is unlikely to change/expand in future books would do the job (as you've already listed above).

Looks good to me.

On the front side of the GM Screen should be a good looking shapely Lady wearing a tight body suit.

I suspect getting everything on you'll need will mean it's 4x2' in size. Better make it out of stiff card...

Well, there are 4 pages to work with. Other than the skills and skill actions (maybe just a list of skills, their action and useable characteristics, and page numbers would suffice. I don't know how to do formatting, but I could take a crack at making the actual content and reporting on size and so on.

I would have a very cut down version of your list. I would cut out anything that the DM should have worked out before a session, such as NPC personalities and exploration rules. I'd also cut out anything that can easily be remembered off like rules for influence and subtitly, rules for hit locations, etc.

Here's my list:
Weapon Qualities
All of the Conditions - Essential
List of the Specialties available from the Specialty Talent (quick way to know if a character shouldn't know something)
List of skills and skill actions - Essential
List of combat actions - Useful so long as it doesn't take up too much space

PRINTOUTS OF THE WOUND TABLES - Yes this is a big problem as these will always need to be referred to and they are pages long.

On the front side of the GM Screen should be a good looking shapely Lady wearing a tight body suit.

Sir! We have a Slaanesh cultist! *blam blam blam*

Sounds like a good list. I'll just add that they should make the screen at least 4 panel so that we can get all the essentials on it. And taller! I need a proper tall screen because with the amount of space I take up behind it, the shorter screens don't conceal enough. Give us a proper big, Imperial-sized screen! 4 panels of 15" high decent cardboard.

Seriously, people who don't want to spend money on things like screens wont buy it just because you make it cheap. The people who are willng, will spend the extra if you make it really good.

I'll certainly welcome all the points mentioned on the list but in a concise format. I totally agree with the weapon table point. On a GM screen this information is totally useless but only takes space.

Wound tables are a must for the GM screen as those tables will be looked up constantly, while also being too large to memorize. Once they are on the screen, will there be any room left for anything else ?

Perhaps have the wound tables on 5 double-sided card sheets (similar to the reference sheets included in the actual Warhammer Fantasy + 40k starter sets), with the 10th side being the description of all the wound conditions and a summary of how to calculate wound values?

As for the main screen, I'd have the Skill and Specialties tables people said, a summary of the AP costs of abilities, weapon qualities, combat modifiers, cover bonuses, and weapon noise for sure.

Wound tables are a must for the GM screen as those tables will be looked up constantly, while also being too large to memorize. Once they are on the screen, will there be any room left for anything else ?

I'd really prefer they weren't. That's nine A4 sides used up for something I'd probably print out anyway. You can shrink them down but then I'm just leaning forward and squinting all evening.

As I mentioned up top, having some print outs of the Wound Tables are basically a must. Would be great if they could double side some of them to include the Psychic Phenomena, and maybe some other less frequently used tables or info (weapons, if they really want to include them, rules on falling, fatigue, healing, etc.)