I use the keyboard as much as possible, and the menu system for 1Password is frustrating because it doesn't define standard menu access keys. In particular, X should be associated with Exit in the File menu. Pretty much every Windows app with a File menu has X as the access key for Exit. I don't know how many times I've typed Alt+F,X to try to exit 1Password just to get beeped at and then had to reach for my mouse.
I've attached a screenshot of Notepad's File menu. Note that if you click on the menu, you won't see the underlined access keys. You need to open the menu with the access key (Alt+F in the case of the file menu). It appears that 1Password doesn't have any access keys defined for its menu items, only the top-level menus. This makes the app harder to use than it should be, both because some standard things don't work and also because my eye is trained to look for the underlined letter. In addition, for menus where there are multiple items that start with the same letter, I have to press the letter multiple times to cycle through those items. However, the behavior changes when some of those items are disabled. That means that I can't always type the same thing to execute the actions, because sometimes I'll have to press a letter twice while other times I have to press it three times.
It's incredibly easy to add access keys for menu items (just put an ampersand in front of the letter in the resources). Please define them for all the menu items in the application. More info here: