Margins when creating a new document in AI and Photoshop
It would save time and be MUCH easier if you could just type in the Margin you want just like you do a bleed when creating a new document just like InDesign. Its time consuming and a pain to drag guides in and make sure that they are Perfect.
You can workaround this by using an action or a template. No need to drag guides manually.
However, I agree that guides should get some improvements, to allow easier setup, like requested here: https://illustrator.uservoice.com/forums/333657/suggestions/41749849