How do you cycle between weapons of the same type and insult or compliment people in GTA 5 on PC?

Solution 1:

You can switch between types of weapons by holding Tab and move the mouse to the desired weapon category on the weapon wheel, then scroll the mouse-wheel to cycle between the guns in that category.

Solution 2:

I'd have thought it was left and right arrow keys but this doesn't seem to be the case and I can't find a button for it in configuration.

Press E according to the Steam forums:

http://steamcommunity.com/app/271590/discussions/0/611703709829902688/

Also, if I have more than 1 weapon in the weapon wheel slot (say if I have an Uzi and an MP5) I can't work out how to easily switch between the 2 minus by pressing the number key for that weapon slot repeatedly. Any ideas?

That is how you switch (as you say) by repeatedly pressing the slot number.