What does this mean?
You know how we have a radar? Of course you do! I suggest that a permanent weapon wheel goes around this thing. It's circular, so it'd fit, right? This would probably shrink while it's not in use, and then grow when you change weapons. If the HUD in unlocked, maybe clicking on a weapon in this wheel would cause you to switch to it, allowing for users to switch weapons with just the mouse, the same way how it's possible to use the tool belt without needing keyboard shortcuts.
And then to go with it, there'd be an option in the Game tab of the options window to remove the weapon wheel that appears next to the characters. This way, users who dislike having the weapon wheel in their face can change it.
EDIT: Fixed typo in Subject.
I propose that instead of having it around the radar, it could partially replace/cover the portrait.