For Arduino part I am adapting Adafruit LED Ampli-Tie project (details here: https://learn.adafruit.com/led-ampli-tie/the-code). In addition I would like to implement several modes for my VU meter which are changed by a button press (e.g. different preset colors). I also want to have a mode where I set a color using a potentiometer and map it's value to RBG color for the strip. Another mode would be nice to have where colors are changing gradually and the speed of color change is set by the same potentiometer.
When I am done with prototyping, I want to put LED strip driver inside my homemade amplifier, have the pot I mentioned, mode changing button, button to on/off VU meter have connectors for wires which connects LED strips to Arduino.