The built-in Button Controller app would be an easy way to do all of these actions (not sure how you have the rest set up). You can choose the "Control Switches, Buttons, Capture/Restore" > "Adjust Dimmer Level" action and enter 10 or -10 to dim up or down by 10%, respectively.
(On a related note, if your buttons support push and release or hold and release and your bulbs/dimmers support the "Start Level Change" and "Stop Level Change" commands, you can do a real-dimmer-like "dim while held"-type thing with the "Start/stop raising/lowering dimmer" actions too!)
ABC Button controller (community app) is also very nice, I've started using that and find it provides a lot of flexible configurations for buttons, really nice.
didnt know that App was there.. Dohh! i have a 4 button hue switch.. does not seem to work as well as expected.. it works. but its a lot of waiting to get the bulbs to go up or down.
I'm using a Lutron Pico remote, and also have an old Minimote button device that I have set up w/Hue bulbs on HE, and the response is quick.
I actually felt (and this could just be subjective bias and not objectively measurable) that the response time for the ABC button controller seemed faster than the built-in button controller app.