The best way to customize the welcome screen is to eliminate it. Under general prefs (command K) there are two columns, the sixth one down (on the left);

unclick the preference that says "Show The Home Screen When No Documents Are Open."

be frustrated no longer.

Seriously, how do we remove A4 from the welcome startup screen?

NOT RESOLVED - A4 is annoying.

Get rid of the Welcome screen... its a window too much... if we want it we should have the option to find it and then open it not the other way around... its so annoying!

You did NOT answer this question. I have the same question.

Colour settings keep reverting to 'Emulate Adobe 6.0' and the colours are showing up way off. For example, bright blues are presenting as violet. When I switch the colour settings to "North America General Purpose 2" everything is corrected - but the moment I minimize the application to use Photoshop or Indesign, the profile reverts back to 'Emulate Adobe 6.0.' Restarting the program doesn't seem to do anything, and neither does saving the settings in Bridge. Very frustrating, as I use many different Creative Cloud applications all day long for work.

Hello Nitish. Thanks for your suggestion but Preferences are out of the way and too "global" for this type of frequent, "on the fly" change. I'm not suggesting anything unknown and "novel" to Adobe as that same capability is, already, partly implemented in Photoshop: File/Open Recent/Clear Recent File List) obviously, not a global preference. So, please add the same capability to Illustrator (and InDesign, etc). Separately, the "Start a new file fast" box is, possibly, something that may be controlled via Preferences panel as I don't believe users would want to mess with that too often after it's setup once. Right now, the EU size A4, not the most used size in the US is off and useless and defeats the "fast" part of the area's name (I'm rather puzzled by Adobe's choice to have this odd standard-size show un n the US). Thank you for your time. A.C.

I'm with Andres! I don't use any of the options that are shown in the "create a new file" section. I want it to show stuff I do use. I don't want to click on a4 and edit it, I don't want it on there at all.

Hi Andres,

There is a way in Illustrator as well to always keep recent files empty.
1. Press Ctrl/Cmd + K
2. Go to File Handling and Clipboard
3. Change the number of recent file in "Number of Recent Files to Display"

On the other to customize Home screen, you can add a feature request.
I hope this helps.

Thanks & Regards
Nitish Agarwal

I appreciate your answer but it's an answer to a different question and hardly addresses (or "resolves") what I wrote:
I'd like to see a way to customize the Welcome screen so I could, for example, place my own shortcuts to my most used types of documents.
Additionally, I'd like to see a way to completely clear the "most recent" files (as one can easily do in Photoshop).
I hope this helps clarify what I wrote originally.
Thank you.

You can do cmd/ctrl + N, select print section and go to A4. You will find the A4 size in the unit you want.