No need to put homelab in quotes, it’s whatever is your lab. We all have different setups that grow and shrink as we learn.
Let me show you a smaller option than a full rack amp. I used this exact setup before except using an AirPort Express instead of the pi.
I would do the Pi (your plan) -> this -> bookshelf speakers like these.
At the same, does “painting our selfs into a corner” loose having true ending to stories?
Constraints and limitations drive creativity, but you have accept a final product at some point and move to another universe/story.