Sounds like you're looking at individually addressable WS2812 aka neopixels.
You're basically replacing the communication with the LEDs (you just tell them what colour they have to be, after that there's no further communication) with communication with an second Arduino (telling it what colour the LEDs should be, after which it will pass on the message to the LEDs).
I don't see any improvement here, really. On the contrary: now you have to implement a communications protocol and program a second controller to read it and put it into the desired LED info. That's much more work for you, while it's not any less (possibly more, actually) work for the host Arduino.