Hi, I'm inclined to agree with that. There are many decent sounding self powered PC speakers. It would simplify your design. Just watch out for ones with a tuned port on the rear. If you build them in the low frequency response will be compromised as the port frequently handles about 1/2 to 2 octaves of bass below the speaker itself. Sealed enclosures do not have this issue but generally either don't go as low in response or require more power (look up Thiel parameters for why). For the lights ...LEDs are now available (and cheap) in strips. They need 12 VDC to operate and a wall wart is just fine for them. I find the sticky back on them is not strong enough for many uses but 3M double sided mounting tape (I like the super strength version) works great. You can really get creative with the LEDs. They come in colors as well and with a suitable controller (also cheap) you can have all sorts of visual effects.

IMO many of which will not improve your computing.
Good listening
Bruce